diff --git a/scintilla/Makefile.am b/scintilla/Makefile.am
index 970807b560..a5b7e9627e 100644
--- a/scintilla/Makefile.am
+++ b/scintilla/Makefile.am
@@ -148,6 +148,7 @@ src/Style.h \
 src/UniConversion.cxx \
 src/UniConversion.h \
 src/UnicodeFromUTF8.h \
+src/UniqueString.cxx \
 src/UniqueString.h \
 src/ViewStyle.cxx \
 src/ViewStyle.h \
diff --git a/scintilla/gtk/Converter.h b/scintilla/gtk/Converter.h
index 0ef80ae23f..eb665b4b6e 100644
--- a/scintilla/gtk/Converter.h
+++ b/scintilla/gtk/Converter.h
@@ -15,24 +15,24 @@ const gsize sizeFailure = static_cast<gsize>(-1);
  */
 class Converter {
 	GIConv iconvh;
-	void OpenHandle(const char *fullDestination, const char *charSetSource) {
+	void OpenHandle(const char *fullDestination, const char *charSetSource) noexcept {
 		iconvh = g_iconv_open(fullDestination, charSetSource);
 	}
-	bool Succeeded() const {
+	bool Succeeded() const noexcept {
 		return iconvh != iconvhBad;
 	}
 public:
-	Converter() {
+	Converter() noexcept {
 		iconvh = iconvhBad;
 	}
 	Converter(const char *charSetDestination, const char *charSetSource, bool transliterations) {
 		iconvh = iconvhBad;
-	    	Open(charSetDestination, charSetSource, transliterations);
+		Open(charSetDestination, charSetSource, transliterations);
 	}
 	~Converter() {
 		Close();
 	}
-	operator bool() const {
+	operator bool() const noexcept {
 		return Succeeded();
 	}
 	void Open(const char *charSetDestination, const char *charSetSource, bool transliterations) {
@@ -50,13 +50,13 @@ class Converter {
 			}
 		}
 	}
-	void Close() {
+	void Close() noexcept {
 		if (Succeeded()) {
 			g_iconv_close(iconvh);
 			iconvh = iconvhBad;
 		}
 	}
-	gsize Convert(char** src, gsize *srcleft, char **dst, gsize *dstleft) const {
+	gsize Convert(char **src, gsize *srcleft, char **dst, gsize *dstleft) const noexcept {
 		if (!Succeeded()) {
 			return sizeFailure;
 		} else {
diff --git a/scintilla/gtk/PlatGTK.cxx b/scintilla/gtk/PlatGTK.cxx
index 26e1b5f583..3e18423dad 100644
--- a/scintilla/gtk/PlatGTK.cxx
+++ b/scintilla/gtk/PlatGTK.cxx
@@ -12,6 +12,7 @@
 #include <string>
 #include <vector>
 #include <map>
+#include <algorithm>
 #include <memory>
 #include <sstream>
 
@@ -26,56 +27,63 @@
 #include "Scintilla.h"
 #include "ScintillaWidget.h"
 #include "StringCopy.h"
+#include "IntegerRectangle.h"
 #include "XPM.h"
 #include "UniConversion.h"
 
 #include "Converter.h"
 
-static const double kPi = 3.14159265358979323846;
+#ifdef _MSC_VER
+// Ignore unreferenced local functions in GTK+ headers
+#pragma warning(disable: 4505)
+#endif
+
+using namespace Scintilla;
+
+namespace {
+
+const double kPi = 3.14159265358979323846;
 
 // The Pango version guard for pango_units_from_double and pango_units_to_double
 // is more complex than simply implementing these here.
 
-static int pangoUnitsFromDouble(double d) {
+int pangoUnitsFromDouble(double d) noexcept {
 	return static_cast<int>(d * PANGO_SCALE + 0.5);
 }
 
-static double doubleFromPangoUnits(int pu) {
-	return static_cast<double>(pu) / PANGO_SCALE;
+float floatFromPangoUnits(int pu) noexcept {
+	return static_cast<float>(pu) / PANGO_SCALE;
 }
 
-static cairo_surface_t *CreateSimilarSurface(GdkWindow *window, cairo_content_t content, int width, int height) {
+cairo_surface_t *CreateSimilarSurface(GdkWindow *window, cairo_content_t content, int width, int height) noexcept {
 	return gdk_window_create_similar_surface(window, content, width, height);
 }
 
-static GdkWindow *WindowFromWidget(GtkWidget *w) {
+GdkWindow *WindowFromWidget(GtkWidget *w) noexcept {
 	return gtk_widget_get_window(w);
 }
 
-#ifdef _MSC_VER
-// Ignore unreferenced local functions in GTK+ headers
-#pragma warning(disable: 4505)
-#endif
-
-using namespace Scintilla;
+GtkWidget *PWidget(WindowID wid) noexcept {
+	return static_cast<GtkWidget *>(wid);
+}
 
-enum encodingType { singleByte, UTF8, dbcs};
+enum encodingType { singleByte, UTF8, dbcs };
 
 // Holds a PangoFontDescription*.
 class FontHandle {
 public:
 	PangoFontDescription *pfd;
 	int characterSet;
-	FontHandle() : pfd(0), characterSet(-1) {
+	FontHandle() noexcept : pfd(nullptr), characterSet(-1) {
 	}
-	FontHandle(PangoFontDescription *pfd_, int characterSet_) {
+	FontHandle(PangoFontDescription *pfd_, int characterSet_) noexcept {
 		pfd = pfd_;
 		characterSet = characterSet_;
 	}
 	~FontHandle() {
 		if (pfd)
 			pango_font_description_free(pfd);
-		pfd = 0;
+		pfd = nullptr;
 	}
 	static FontHandle *CreateNewFont(const FontParameters &fp);
 };
@@ -88,24 +96,22 @@ FontHandle *FontHandle::CreateNewFont(const FontParameters &fp) {
 		pango_font_description_set_size(pfd, pangoUnitsFromDouble(fp.size));
 		pango_font_description_set_weight(pfd, static_cast<PangoWeight>(fp.weight));
 		pango_font_description_set_style(pfd, fp.italic ? PANGO_STYLE_ITALIC : PANGO_STYLE_NORMAL);
-		return new FontHandle(pfd,fp.characterSet);
+		return new FontHandle(pfd, fp.characterSet);
 	}
 
-	return NULL;
+	return nullptr;
 }
 
 // X has a 16 bit coordinate space, so stop drawing here to avoid wrapping
-static const int maxCoordinate = 32000;
+const int maxCoordinate = 32000;
 
-static FontHandle *PFont(Font &f) {
+FontHandle *PFont(const Font &f) noexcept {
 	return static_cast<FontHandle *>(f.GetID());
 }
 
-static GtkWidget *PWidget(WindowID wid) {
-	return static_cast<GtkWidget *>(wid);
 }
 
-Font::Font() noexcept : fid(0) {}
+Font::Font() noexcept : fid(nullptr) {}
 
 Font::~Font() {}
 
@@ -117,7 +123,7 @@ void Font::Create(const FontParameters &fp) {
 void Font::Release() {
 	if (fid)
 		delete static_cast<FontHandle *>(fid);
-	fid = 0;
+	fid = nullptr;
 }
 
 // Required on OS X
@@ -138,14 +144,14 @@ class SurfaceImpl : public Surface {
 	int characterSet;
 	void SetConverter(int characterSet_);
 public:
-	SurfaceImpl();
+	SurfaceImpl() noexcept;
 	~SurfaceImpl() override;
 
 	void Init(WindowID wid) override;
 	void Init(SurfaceID sid, WindowID wid) override;
 	void InitPixMap(int width, int height, Surface *surface_, WindowID wid) override;
 
-	void Clear();
+	void Clear() noexcept;
 	void Release() override;
 	bool Initialised() override;
 	void PenColour(ColourDesired fore) override;
@@ -185,7 +191,7 @@ class SurfaceImpl : public Surface {
 };
 }
 
-const char *CharacterSetID(int characterSet) {
+const char *CharacterSetID(int characterSet) noexcept {
 	switch (characterSet) {
 	case SC_CHARSET_ANSI:
 		return "";
@@ -243,33 +249,33 @@ void SurfaceImpl::SetConverter(int characterSet_) {
 	}
 }
 
-SurfaceImpl::SurfaceImpl() : et(singleByte),
-context(0),
-psurf(0),
-x(0), y(0), inited(false), createdGC(false)
-, pcontext(0), layout(0), characterSet(-1) {
+SurfaceImpl::SurfaceImpl() noexcept : et(singleByte),
+context(nullptr),
+psurf(nullptr),
+x(0), y(0), inited(false), createdGC(false),
+pcontext(nullptr), layout(nullptr), characterSet(-1) {
 }
 
 SurfaceImpl::~SurfaceImpl() {
 	Clear();
 }
 
-void SurfaceImpl::Clear() {
+void SurfaceImpl::Clear() noexcept {
 	et = singleByte;
 	if (createdGC) {
 		createdGC = false;
 		cairo_destroy(context);
 	}
-	context = 0;
+	context = nullptr;
 	if (psurf)
 		cairo_surface_destroy(psurf);
-	psurf = 0;
+	psurf = nullptr;
 	if (layout)
 		g_object_unref(layout);
-	layout = 0;
+	layout = nullptr;
 	if (pcontext)
 		g_object_unref(pcontext);
-	pcontext = 0;
+	pcontext = nullptr;
 	conv.Close();
 	characterSet = -1;
 	x = 0;
@@ -306,8 +312,8 @@ void SurfaceImpl::Init(WindowID wid) {
 	Release();
 	PLATFORM_ASSERT(wid);
 	// if we are only created from a window ID, we can't perform drawing
-	psurf = 0;
-	context = 0;
+	psurf = nullptr;
+	context = nullptr;
 	createdGC = false;
 	pcontext = gtk_widget_create_pango_context(PWidget(wid));
 	PLATFORM_ASSERT(pcontext);
@@ -361,7 +367,7 @@ void SurfaceImpl::InitPixMap(int width, int height, Surface *surface_, WindowID
 
 void SurfaceImpl::PenColour(ColourDesired fore) {
 	if (context) {
-		ColourDesired cdFore(fore.AsInteger());
+		const ColourDesired cdFore(fore.AsInteger());
 		cairo_set_source_rgb(context,
 			cdFore.GetRed() / 255.0,
 			cdFore.GetGreen() / 255.0,
@@ -374,7 +380,7 @@ int SurfaceImpl::LogPixelsY() {
 }
 
 int SurfaceImpl::DeviceHeightFont(int points) {
-	int logPix = LogPixelsY();
+	const int logPix = LogPixelsY();
 	return (points * logPix + logPix / 2) / 72;
 }
 
@@ -383,7 +389,7 @@ void SurfaceImpl::MoveTo(int x_, int y_) {
 	y = y_;
 }
 
-static int Delta(int difference) {
+static int Delta(int difference) noexcept {
 	if (difference < 0)
 		return -1;
 	else if (difference > 0)
@@ -396,21 +402,21 @@ void SurfaceImpl::LineTo(int x_, int y_) {
 	// cairo_line_to draws the end position, unlike Win32 or GDK with GDK_CAP_NOT_LAST.
 	// For simple cases, move back one pixel from end.
 	if (context) {
-		int xDiff = x_ - x;
-		int xDelta = Delta(xDiff);
-		int yDiff = y_ - y;
-		int yDelta = Delta(yDiff);
+		const int xDiff = x_ - x;
+		const int xDelta = Delta(xDiff);
+		const int yDiff = y_ - y;
+		const int yDelta = Delta(yDiff);
 		if ((xDiff == 0) || (yDiff == 0)) {
 			// Horizontal or vertical lines can be more precisely drawn as a filled rectangle
-			int xEnd = x_ - xDelta;
-			int left = std::min(x, xEnd);
-			int width = abs(x - xEnd) + 1;
-			int yEnd = y_ - yDelta;
-			int top = std::min(y, yEnd);
-			int height = abs(y - yEnd) + 1;
+			const int xEnd = x_ - xDelta;
+			const int left = std::min(x, xEnd);
+			const int width = std::abs(x - xEnd) + 1;
+			const int yEnd = y_ - yDelta;
+			const int top = std::min(y, yEnd);
+			const int height = std::abs(y - yEnd) + 1;
 			cairo_rectangle(context, left, top, width, height);
 			cairo_fill(context);
-		} else if ((abs(xDiff) == abs(yDiff))) {
+		} else if ((std::abs(xDiff) == std::abs(yDiff))) {
 			// 45 degree slope
 			cairo_move_to(context, x + 0.5, y + 0.5);
 			cairo_line_to(context, x_ + 0.5 - xDelta, y_ + 0.5 - yDelta);
@@ -453,8 +459,8 @@ void SurfaceImpl::RectangleDraw(PRectangle rc, ColourDesired fore, ColourDesired
 void SurfaceImpl::FillRectangle(PRectangle rc, ColourDesired back) {
 	PenColour(back);
 	if (context && (rc.left < maxCoordinate)) {	// Protect against out of range
-		rc.left = lround(rc.left);
-		rc.right = lround(rc.right);
+		rc.left = std::round(rc.left);
+		rc.right = std::round(rc.right);
 		cairo_rectangle(context, rc.left, rc.top,
 	                     rc.right - rc.left, rc.bottom - rc.top);
 		cairo_fill(context);
@@ -463,17 +469,18 @@ void SurfaceImpl::FillRectangle(PRectangle rc, ColourDesired back) {
 
 void SurfaceImpl::FillRectangle(PRectangle rc, Surface &surfacePattern) {
 	SurfaceImpl &surfi = static_cast<SurfaceImpl &>(surfacePattern);
-	bool canDraw = surfi.psurf != NULL;
+	const bool canDraw = surfi.psurf != nullptr;
 	if (canDraw) {
 		PLATFORM_ASSERT(context);
 		// Tile pattern over rectangle
 		// Currently assumes 8x8 pattern
-		int widthPat = 8;
-		int heightPat = 8;
-		for (int xTile = rc.left; xTile < rc.right; xTile += widthPat) {
-			int widthx = (xTile + widthPat > rc.right) ? rc.right - xTile : widthPat;
-			for (int yTile = rc.top; yTile < rc.bottom; yTile += heightPat) {
-				int heighty = (yTile + heightPat > rc.bottom) ? rc.bottom - yTile : heightPat;
+		const int widthPat = 8;
+		const int heightPat = 8;
+		const IntegerRectangle irc(rc);
+		for (int xTile = irc.left; xTile < irc.right; xTile += widthPat) {
+			const int widthx = (xTile + widthPat > irc.right) ? irc.right - xTile : widthPat;
+			for (int yTile = irc.top; yTile < irc.bottom; yTile += heightPat) {
+				const int heighty = (yTile + heightPat > irc.bottom) ? irc.bottom - yTile : heightPat;
 				cairo_set_source_surface(context, surfi.psurf, xTile, yTile);
 				cairo_rectangle(context, xTile, yTile, widthx, heighty);
 				cairo_fill(context);
@@ -505,8 +512,8 @@ void SurfaceImpl::RoundedRectangle(PRectangle rc, ColourDesired fore, ColourDesi
 	}
 }
 
-static void PathRoundRectangle(cairo_t *context, double left, double top, double width, double height, int radius) {
-	double degrees = kPi / 180.0;
+static void PathRoundRectangle(cairo_t *context, double left, double top, double width, double height, int radius) noexcept {
+	const double degrees = kPi / 180.0;
 
 	cairo_new_sub_path(context);
 	cairo_arc(context, left + width - radius, top + radius, radius, -90 * degrees, 0 * degrees);
@@ -519,7 +526,7 @@ static void PathRoundRectangle(cairo_t *context, double left, double top, double
 void SurfaceImpl::AlphaRectangle(PRectangle rc, int cornerSize, ColourDesired fill, int alphaFill,
 		ColourDesired outline, int alphaOutline, int /*flags*/) {
 	if (context && rc.Width() > 0) {
-		ColourDesired cdFill(fill.AsInteger());
+		const ColourDesired cdFill(fill.AsInteger());
 		cairo_set_source_rgba(context,
 			cdFill.GetRed() / 255.0,
 			cdFill.GetGreen() / 255.0,
@@ -531,7 +538,7 @@ void SurfaceImpl::AlphaRectangle(PRectangle rc, int cornerSize, ColourDesired fi
 			cairo_rectangle(context, rc.left + 1.0, rc.top + 1.0, rc.right - rc.left - 2.0, rc.bottom - rc.top - 2.0);
 		cairo_fill(context);
 
-		ColourDesired cdOutline(outline.AsInteger());
+		const ColourDesired cdOutline(outline.AsInteger());
 		cairo_set_source_rgba(context,
 			cdOutline.GetRed() / 255.0,
 			cdOutline.GetGreen() / 255.0,
@@ -581,12 +588,12 @@ void SurfaceImpl::DrawRGBAImage(PRectangle rc, int width, int height, const unsi
 	rc.bottom = rc.top + height;
 
 	int stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, width);
-	int ucs = stride * height;
+	const int ucs = stride * height;
 	std::vector<unsigned char> image(ucs);
 	for (int iy=0; iy<height; iy++) {
 		for (int ix=0; ix<width; ix++) {
 			unsigned char *pixel = &image[0] + iy*stride + ix * 4;
-			unsigned char alpha = pixelsImage[3];
+			const unsigned char alpha = pixelsImage[3];
 			pixel[2] = (*pixelsImage++) * alpha / 255;
 			pixel[1] = (*pixelsImage++) * alpha / 255;
 			pixel[0] = (*pixelsImage++) * alpha / 255;
@@ -614,7 +621,7 @@ void SurfaceImpl::Ellipse(PRectangle rc, ColourDesired fore, ColourDesired back)
 
 void SurfaceImpl::Copy(PRectangle rc, Point from, Surface &surfaceSource) {
 	SurfaceImpl &surfi = static_cast<SurfaceImpl &>(surfaceSource);
-	bool canDraw = surfi.psurf != NULL;
+	const bool canDraw = surfi.psurf != nullptr;
 	if (canDraw) {
 		PLATFORM_ASSERT(context);
 		cairo_set_source_surface(context, surfi.psurf,
@@ -648,7 +655,7 @@ static std::string UTF8FromIconv(const Converter &conv, const char *s, int len)
 		char *putf = &utfForm[0];
 		char *pout = putf;
 		gsize outLeft = len*3+1;
-		gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
+		const gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
 		if (conversions != sizeFailure) {
 			*pout = '\0';
 			utfForm.resize(pout - putf);
@@ -667,7 +674,7 @@ static size_t MultiByteLenFromIconv(const Converter &conv, const char *s, size_t
 		gsize inLeft = lenMB;
 		char *pout = wcForm;
 		gsize outLeft = 2;
-		gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
+		const gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
 		if (conversions != sizeFailure) {
 			return lenMB;
 		}
@@ -679,7 +686,7 @@ void SurfaceImpl::DrawTextBase(PRectangle rc, Font &font_, XYPOSITION ybase, con
                                  ColourDesired fore) {
 	PenColour(fore);
 	if (context) {
-		XYPOSITION xText = rc.left;
+		const XYPOSITION xText = rc.left;
 		if (PFont(font_)->pfd) {
 			std::string utfForm;
 			if (et == UTF8) {
@@ -694,7 +701,7 @@ void SurfaceImpl::DrawTextBase(PRectangle rc, Font &font_, XYPOSITION ybase, con
 			}
 			pango_layout_set_font_description(layout, PFont(font_)->pfd);
 			pango_cairo_update_layout(context, layout);
-			PangoLayoutLine *pll = pango_layout_get_line_readonly(layout,0);
+			PangoLayoutLine *pll = pango_layout_get_line_readonly(layout, 0);
 			cairo_move_to(context, xText, ybase);
 			pango_cairo_show_layout_line(context, pll);
 		}
@@ -735,24 +742,24 @@ class ClusterIterator {
 	XYPOSITION position;
 	XYPOSITION distance;
 	int curIndex;
-	ClusterIterator(PangoLayout *layout, int len) : lenPositions(len), finished(false),
+	ClusterIterator(PangoLayout *layout, int len) noexcept : lenPositions(len), finished(false),
 		positionStart(0), position(0), distance(0), curIndex(0) {
 		iter = pango_layout_get_iter(layout);
-		pango_layout_iter_get_cluster_extents(iter, NULL, &pos);
+		pango_layout_iter_get_cluster_extents(iter, nullptr, &pos);
 	}
 	~ClusterIterator() {
 		pango_layout_iter_free(iter);
 	}
 
-	void Next() {
+	void Next() noexcept {
 		positionStart = position;
 		if (pango_layout_iter_next_cluster(iter)) {
-			pango_layout_iter_get_cluster_extents(iter, NULL, &pos);
-			position = doubleFromPangoUnits(pos.x);
+			pango_layout_iter_get_cluster_extents(iter, nullptr, &pos);
+			position = floatFromPangoUnits(pos.x);
 			curIndex = pango_layout_iter_get_index(iter);
 		} else {
 			finished = true;
-			position = doubleFromPangoUnits(pos.x + pos.width);
+			position = floatFromPangoUnits(pos.x + pos.width);
 			curIndex = lenPositions;
 		}
 		distance = position - positionStart;
@@ -771,7 +778,7 @@ void SurfaceImpl::MeasureWidths(Font &font_, const char *s, int len, XYPOSITION
 				ClusterIterator iti(layout, lenPositions);
 				while (!iti.finished) {
 					iti.Next();
-					int places = iti.curIndex - i;
+					const int places = iti.curIndex - i;
 					while (i < iti.curIndex) {
 						// Evenly distribute space among bytes of this cluster.
 						// Would be better to find number of characters and then
@@ -798,8 +805,8 @@ void SurfaceImpl::MeasureWidths(Font &font_, const char *s, int len, XYPOSITION
 						ClusterIterator iti(layout, strlen(utfForm.c_str()));
 						while (!iti.finished) {
 							iti.Next();
-							int clusterEnd = iti.curIndex;
-							int places = g_utf8_strlen(utfForm.c_str() + clusterStart, clusterEnd - clusterStart);
+							const int clusterEnd = iti.curIndex;
+							const int places = g_utf8_strlen(utfForm.c_str() + clusterStart, clusterEnd - clusterStart);
 							int place = 1;
 							while (clusterStart < clusterEnd) {
 								size_t lenChar = MultiByteLenFromIconv(convMeasure, s+i, len-i);
@@ -814,7 +821,7 @@ void SurfaceImpl::MeasureWidths(Font &font_, const char *s, int len, XYPOSITION
 						PLATFORM_ASSERT(i == lenPositions);
 					}
 				}
-				if (positionsCalculated < 1 ) {
+				if (positionsCalculated < 1) {
 					// Either 8-bit or DBCS conversion failed so treat as 8-bit.
 					SetConverter(PFont(font_)->characterSet);
 					const bool rtlCheck = PFont(font_)->characterSet == SC_CHARSET_HEBREW ||
@@ -831,13 +838,13 @@ void SurfaceImpl::MeasureWidths(Font &font_, const char *s, int len, XYPOSITION
 					ClusterIterator iti(layout, utfForm.length());
 					while (!iti.finished) {
 						iti.Next();
-						int clusterEnd = iti.curIndex;
-						int ligatureLength = g_utf8_strlen(utfForm.c_str() + clusterStart, clusterEnd - clusterStart);
+						const int clusterEnd = iti.curIndex;
+						const int ligatureLength = g_utf8_strlen(utfForm.c_str() + clusterStart, clusterEnd - clusterStart);
 						if (rtlCheck && ((clusterEnd <= clusterStart) || (ligatureLength == 0) || (ligatureLength > 3))) {
 							// Something has gone wrong: exit quickly but pretend all the characters are equally spaced:
 							int widthLayout = 0;
-							pango_layout_get_size(layout, &widthLayout, NULL);
-							XYPOSITION widthTotal = doubleFromPangoUnits(widthLayout);
+							pango_layout_get_size(layout, &widthLayout, nullptr);
+							const XYPOSITION widthTotal = floatFromPangoUnits(widthLayout);
 							for (int bytePos=0; bytePos<lenPositions; bytePos++) {
 								positions[bytePos] = widthTotal / lenPositions * (bytePos + 1);
 							}
@@ -881,9 +888,9 @@ XYPOSITION SurfaceImpl::WidthText(Font &font_, const char *s, int len) {
 				}
 				pango_layout_set_text(layout, utfForm.c_str(), utfForm.length());
 			}
-			PangoLayoutLine *pangoLine = pango_layout_get_line_readonly(layout,0);
-			pango_layout_line_get_extents(pangoLine, NULL, &pos);
-			return doubleFromPangoUnits(pos.width);
+			PangoLayoutLine *pangoLine = pango_layout_get_line_readonly(layout, 0);
+			pango_layout_line_get_extents(pangoLine, nullptr, &pos);
+			return floatFromPangoUnits(pos.width);
 		}
 		return 1;
 	} else {
@@ -896,12 +903,12 @@ XYPOSITION SurfaceImpl::WidthText(Font &font_, const char *s, int len) {
 XYPOSITION SurfaceImpl::Ascent(Font &font_) {
 	if (!(font_.GetID()))
 		return 1;
-	int ascent = 0;
+	XYPOSITION ascent = 0;
 	if (PFont(font_)->pfd) {
 		PangoFontMetrics *metrics = pango_context_get_metrics(pcontext,
 			PFont(font_)->pfd, pango_context_get_language(pcontext));
-		ascent =
-			doubleFromPangoUnits(pango_font_metrics_get_ascent(metrics));
+		ascent = std::floor(floatFromPangoUnits(
+			pango_font_metrics_get_ascent(metrics)));
 		pango_font_metrics_unref(metrics);
 	}
 	if (ascent == 0) {
@@ -916,7 +923,8 @@ XYPOSITION SurfaceImpl::Descent(Font &font_) {
 	if (PFont(font_)->pfd) {
 		PangoFontMetrics *metrics = pango_context_get_metrics(pcontext,
 			PFont(font_)->pfd, pango_context_get_language(pcontext));
-		int descent = doubleFromPangoUnits(pango_font_metrics_get_descent(metrics));
+		const XYPOSITION descent = std::floor(floatFromPangoUnits(
+			pango_font_metrics_get_descent(metrics)));
 		pango_font_metrics_unref(metrics);
 		return descent;
 	}
@@ -961,7 +969,7 @@ Window::~Window() {}
 
 void Window::Destroy() {
 	if (wid) {
-		ListBox *listbox = dynamic_cast<ListBox*>(this);
+		ListBox *listbox = dynamic_cast<ListBox *>(this);
 		if (listbox) {
 			gtk_widget_hide(GTK_WIDGET(wid));
 			// clear up window content
@@ -972,7 +980,7 @@ void Window::Destroy() {
 		} else {
 			gtk_widget_destroy(GTK_WIDGET(wid));
 		}
-		wid = 0;
+		wid = nullptr;
 	}
 }
 
@@ -982,8 +990,8 @@ PRectangle Window::GetPosition() const {
 	if (wid) {
 		GtkAllocation allocation;
 		gtk_widget_get_allocation(PWidget(wid), &allocation);
-		rc.left = allocation.x;
-		rc.top = allocation.y;
+		rc.left = static_cast<XYPOSITION>(allocation.x);
+		rc.top = static_cast<XYPOSITION>(allocation.y);
 		if (allocation.width > 20) {
 			rc.right = rc.left + allocation.width;
 			rc.bottom = rc.top + allocation.height;
@@ -994,10 +1002,10 @@ PRectangle Window::GetPosition() const {
 
 void Window::SetPosition(PRectangle rc) {
 	GtkAllocation alloc;
-	alloc.x = rc.left;
-	alloc.y = rc.top;
-	alloc.width = rc.Width();
-	alloc.height = rc.Height();
+	alloc.x = static_cast<int>(rc.left);
+	alloc.y = static_cast<int>(rc.top);
+	alloc.width = static_cast<int>(rc.Width());
+	alloc.height = static_cast<int>(rc.Height());
 	gtk_widget_size_allocate(PWidget(wid), &alloc);
 }
 
@@ -1011,8 +1019,8 @@ GdkRectangle MonitorRectangleForWidget(GtkWidget *wid) {
 	GdkMonitor *monitor = gdk_display_get_monitor_at_window(pdisplay, wnd);
 	gdk_monitor_get_geometry(monitor, &rcScreen);
 #else
-	GdkScreen* screen = gtk_widget_get_screen(wid);
-	gint monitor_num = gdk_screen_get_monitor_at_window(screen, wnd);
+	GdkScreen *screen = gtk_widget_get_screen(wid);
+	const gint monitor_num = gdk_screen_get_monitor_at_window(screen, wnd);
 	gdk_screen_get_monitor_geometry(screen, monitor_num, &rcScreen);
 #endif
 	return rcScreen;
@@ -1021,18 +1029,19 @@ GdkRectangle MonitorRectangleForWidget(GtkWidget *wid) {
 }
 
 void Window::SetPositionRelative(PRectangle rc, const Window *relativeTo) {
+	const IntegerRectangle irc(rc);
 	int ox = 0;
 	int oy = 0;
 	GdkWindow *wndRelativeTo = WindowFromWidget(PWidget(relativeTo->wid));
 	gdk_window_get_origin(wndRelativeTo, &ox, &oy);
-	ox += rc.left;
-	oy += rc.top;
+	ox += irc.left;
+	oy += irc.top;
 
-	GdkRectangle rcMonitor = MonitorRectangleForWidget(PWidget(relativeTo->wid));
+	const GdkRectangle rcMonitor = MonitorRectangleForWidget(PWidget(relativeTo->wid));
 
 	/* do some corrections to fit into screen */
-	int sizex = rc.right - rc.left;
-	int sizey = rc.bottom - rc.top;
+	const int sizex = irc.Width();
+	const int sizey = irc.Height();
 	if (sizex > rcMonitor.width || ox < rcMonitor.x)
 		ox = rcMonitor.x; /* the best we can do */
 	else if (ox + sizex > rcMonitor.x + rcMonitor.width)
@@ -1065,9 +1074,10 @@ void Window::InvalidateAll() {
 
 void Window::InvalidateRectangle(PRectangle rc) {
 	if (wid) {
+		const IntegerRectangle irc(rc);
 		gtk_widget_queue_draw_area(PWidget(wid),
-		                           rc.left, rc.top,
-		                           rc.right - rc.left, rc.bottom - rc.top);
+		                           irc.left, irc.top,
+		                           irc.Width(), irc.Height());
 	}
 }
 
@@ -1134,24 +1144,24 @@ PRectangle Window::GetMonitorRect(Point pt) {
 		pt.x + x_offset, pt.y + y_offset);
 	gdk_monitor_get_geometry(monitor, &rect);
 #else
-	GdkScreen* screen = gtk_widget_get_screen(PWidget(wid));
-	gint monitor_num = gdk_screen_get_monitor_at_point(screen,
+	GdkScreen *screen = gtk_widget_get_screen(PWidget(wid));
+	const gint monitor_num = gdk_screen_get_monitor_at_point(screen,
 		pt.x + x_offset, pt.y + y_offset);
 	gdk_screen_get_monitor_geometry(screen, monitor_num, &rect);
 #endif
 	rect.x -= x_offset;
 	rect.y -= y_offset;
-	return PRectangle(rect.x, rect.y, rect.x + rect.width, rect.y + rect.height);
+	return PRectangle::FromInts(rect.x, rect.y, rect.x + rect.width, rect.y + rect.height);
 }
 
-typedef std::map<int, RGBAImage*> ImageMap;
+typedef std::map<int, RGBAImage *> ImageMap;
 
 struct ListImage {
 	const RGBAImage *rgba_data;
 	GdkPixbuf *pixbuf;
 };
 
-static void list_image_free(gpointer, gpointer value, gpointer) {
+static void list_image_free(gpointer, gpointer value, gpointer) noexcept {
 	ListImage *list_image = static_cast<ListImage *>(value);
 	if (list_image->pixbuf)
 		g_object_unref(list_image->pixbuf);
@@ -1176,8 +1186,8 @@ class ListBoxX : public ListBox {
 	WindowID list;
 	WindowID scroller;
 	void *pixhash;
-	GtkCellRenderer* pixbuf_renderer;
-	GtkCellRenderer* renderer;
+	GtkCellRenderer *pixbuf_renderer;
+	GtkCellRenderer *renderer;
 	RGBAImageSet images;
 	int desiredVisibleRows;
 	unsigned int maxItemCharacters;
@@ -1188,28 +1198,29 @@ class ListBoxX : public ListBox {
 public:
 	IListBoxDelegate *delegate;
 
-	ListBoxX() : widCached(0), frame(0), list(0), scroller(0), pixhash(NULL), pixbuf_renderer(0),
-		renderer(0),
+	ListBoxX() noexcept : widCached(nullptr), frame(nullptr), list(nullptr), scroller(nullptr),
+		pixhash(nullptr), pixbuf_renderer(nullptr),
+		renderer(nullptr),
 		desiredVisibleRows(5), maxItemCharacters(0),
 		aveCharWidth(1),
 #if GTK_CHECK_VERSION(3,0,0)
-		cssProvider(NULL),
+		cssProvider(nullptr),
 #endif
 		delegate(nullptr) {
 	}
 	~ListBoxX() override {
 		if (pixhash) {
-			g_hash_table_foreach((GHashTable *) pixhash, list_image_free, NULL);
+			g_hash_table_foreach((GHashTable *) pixhash, list_image_free, nullptr);
 			g_hash_table_destroy((GHashTable *) pixhash);
 		}
 		if (widCached) {
 			gtk_widget_destroy(GTK_WIDGET(widCached));
-			wid = widCached = 0;
+			wid = widCached = nullptr;
 		}
 #if GTK_CHECK_VERSION(3,0,0)
 		if (cssProvider) {
 			g_object_unref(cssProvider);
-			cssProvider = NULL;
+			cssProvider = nullptr;
 		}
 #endif
 	}
@@ -1247,7 +1258,7 @@ static int treeViewGetRowHeight(GtkTreeView *view) {
 	// version is inaccurate for GTK 3.14.
 	GdkRectangle rect;
 	GtkTreePath *path = gtk_tree_path_new_first();
-	gtk_tree_view_get_background_area(view, path, NULL, &rect);
+	gtk_tree_view_get_background_area(view, path, nullptr, &rect);
 	gtk_tree_path_free(path);
 	return rect.height;
 #else
@@ -1255,10 +1266,10 @@ static int treeViewGetRowHeight(GtkTreeView *view) {
 	int vertical_separator=0;
 	int expander_size=0;
 	GtkTreeViewColumn *column = gtk_tree_view_get_column(view, 0);
-	gtk_tree_view_column_cell_get_size(column, NULL, NULL, NULL, NULL, &row_height);
+	gtk_tree_view_column_cell_get_size(column, nullptr, nullptr, nullptr, nullptr, &row_height);
 	gtk_widget_style_get(GTK_WIDGET(view),
 		"vertical-separator", &vertical_separator,
-		"expander-size", &expander_size, NULL);
+		"expander-size", &expander_size, nullptr);
 	row_height += vertical_separator;
 	row_height = std::max(row_height, expander_size);
 	return row_height;
@@ -1292,7 +1303,7 @@ static void small_scroller_get_preferred_height(GtkWidget *widget, gint *min, gi
 	GtkWidget *child = gtk_bin_get_child(GTK_BIN(widget));
 	if (GTK_IS_TREE_VIEW(child)) {
 		GtkTreeModel *model = gtk_tree_view_get_model(GTK_TREE_VIEW(child));
-		int n_rows = gtk_tree_model_iter_n_children(model, NULL);
+		int n_rows = gtk_tree_model_iter_n_children(model, nullptr);
 		int row_height = treeViewGetRowHeight(GTK_TREE_VIEW(child));
 
 		*min = MAX(1, row_height);
@@ -1318,11 +1329,11 @@ static void small_scroller_class_init(SmallScrollerClass *klass) {
 #endif
 }
 
-static void small_scroller_init(SmallScroller *){}
+static void small_scroller_init(SmallScroller *) {}
 
-static gboolean ButtonPress(GtkWidget *, GdkEventButton* ev, gpointer p) {
+static gboolean ButtonPress(GtkWidget *, GdkEventButton *ev, gpointer p) {
 	try {
-		ListBoxX* lb = static_cast<ListBoxX*>(p);
+		ListBoxX *lb = static_cast<ListBoxX *>(p);
 		if (ev->type == GDK_2BUTTON_PRESS && lb->delegate) {
 			ListBoxEvent event(ListBoxEvent::EventType::doubleClick);
 			lb->delegate->ListNotify(&event);
@@ -1335,9 +1346,9 @@ static gboolean ButtonPress(GtkWidget *, GdkEventButton* ev, gpointer p) {
 	return FALSE;
 }
 
-static gboolean ButtonRelease(GtkWidget *, GdkEventButton* ev, gpointer p) {
+static gboolean ButtonRelease(GtkWidget *, GdkEventButton *ev, gpointer p) {
 	try {
-		ListBoxX* lb = static_cast<ListBoxX*>(p);
+		ListBoxX *lb = static_cast<ListBoxX *>(p);
 		if (ev->type != GDK_2BUTTON_PRESS && lb->delegate) {
 			ListBoxEvent event(ListBoxEvent::EventType::selectionChange);
 			lb->delegate->ListNotify(&event);
@@ -1351,9 +1362,9 @@ static gboolean ButtonRelease(GtkWidget *, GdkEventButton* ev, gpointer p) {
 
 /* Change the active color to the selected color so the listbox uses the color
 scheme that it would use if it had the focus. */
-static void StyleSet(GtkWidget *w, GtkStyle*, void*) {
+static void StyleSet(GtkWidget *w, GtkStyle *, void *) {
 
-	g_return_if_fail(w != NULL);
+	g_return_if_fail(w != nullptr);
 
 	/* Copy the selected color to active.  Note that the modify calls will cause
 	recursive calls to this function after the value is updated and w->style to
@@ -1365,7 +1376,7 @@ static void StyleSet(GtkWidget *w, GtkStyle*, void*) {
 	// The *override* calls are deprecated now, so only call them for older versions of GTK+.
 #elif GTK_CHECK_VERSION(3,0,0)
 	GtkStyleContext *styleContext = gtk_widget_get_style_context(w);
-	if (styleContext == NULL)
+	if (styleContext == nullptr)
 		return;
 
 	GdkRGBA colourForeSelected;
@@ -1376,7 +1387,7 @@ static void StyleSet(GtkWidget *w, GtkStyle*, void*) {
 		gtk_widget_override_color(w, GTK_STATE_FLAG_ACTIVE, &colourForeSelected);
 
 	styleContext = gtk_widget_get_style_context(w);
-	if (styleContext == NULL)
+	if (styleContext == nullptr)
 		return;
 
 	GdkRGBA colourBaseSelected;
@@ -1387,12 +1398,12 @@ static void StyleSet(GtkWidget *w, GtkStyle*, void*) {
 		gtk_widget_override_background_color(w, GTK_STATE_FLAG_ACTIVE, &colourBaseSelected);
 #else
 	GtkStyle *style = gtk_widget_get_style(w);
-	if (style == NULL)
+	if (style == nullptr)
 		return;
 	if (!gdk_color_equal(&style->base[GTK_STATE_SELECTED], &style->base[GTK_STATE_ACTIVE]))
 		gtk_widget_modify_base(w, GTK_STATE_ACTIVE, &style->base[GTK_STATE_SELECTED]);
 	style = gtk_widget_get_style(w);
-	if (style == NULL)
+	if (style == nullptr)
 		return;
 	if (!gdk_color_equal(&style->text[GTK_STATE_SELECTED], &style->text[GTK_STATE_ACTIVE]))
 		gtk_widget_modify_text(w, GTK_STATE_ACTIVE, &style->text[GTK_STATE_SELECTED]);
@@ -1400,7 +1411,7 @@ static void StyleSet(GtkWidget *w, GtkStyle*, void*) {
 }
 
 void ListBoxX::Create(Window &parent, int, Point, int, bool, int) {
-	if (widCached != 0) {
+	if (widCached != nullptr) {
 		wid = widCached;
 		return;
 	}
@@ -1413,13 +1424,13 @@ void ListBoxX::Create(Window &parent, int, Point, int, bool, int) {
 
 	wid = widCached = gtk_window_new(GTK_WINDOW_POPUP);
 
-	frame = gtk_frame_new(NULL);
+	frame = gtk_frame_new(nullptr);
 	gtk_widget_show(PWidget(frame));
 	gtk_container_add(GTK_CONTAINER(GetID()), PWidget(frame));
 	gtk_frame_set_shadow_type(GTK_FRAME(frame), GTK_SHADOW_OUT);
 	gtk_container_set_border_width(GTK_CONTAINER(frame), 0);
 
-	scroller = g_object_new(small_scroller_get_type(), NULL);
+	scroller = g_object_new(small_scroller_get_type(), nullptr);
 	gtk_container_set_border_width(GTK_CONTAINER(scroller), 0);
 	gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scroller),
 	                               GTK_POLICY_NEVER, GTK_POLICY_AUTOMATIC);
@@ -1431,7 +1442,7 @@ void ListBoxX::Create(Window &parent, int, Point, int, bool, int) {
 		gtk_list_store_new(N_COLUMNS, GDK_TYPE_PIXBUF, G_TYPE_STRING);
 
 	list = gtk_tree_view_new_with_model(GTK_TREE_MODEL(store));
-	g_signal_connect(G_OBJECT(list), "style-set", G_CALLBACK(StyleSet), NULL);
+	g_signal_connect(G_OBJECT(list), "style-set", G_CALLBACK(StyleSet), nullptr);
 
 #if GTK_CHECK_VERSION(3,0,0)
 	GtkStyleContext *styleContext = gtk_widget_get_style_context(GTK_WIDGET(list));
@@ -1466,7 +1477,7 @@ void ListBoxX::Create(Window &parent, int, Point, int, bool, int) {
 
 	gtk_tree_view_append_column(GTK_TREE_VIEW(list), column);
 	if (g_object_class_find_property(G_OBJECT_GET_CLASS(list), "fixed-height-mode"))
-		g_object_set(G_OBJECT(list), "fixed-height-mode", TRUE, NULL);
+		g_object_set(G_OBJECT(list), "fixed-height-mode", TRUE, nullptr);
 
 	GtkWidget *widget = PWidget(list);	// No code inside the G_OBJECT macro
 	gtk_container_add(GTK_CONTAINER(PWidget(scroller)), widget);
@@ -1496,7 +1507,7 @@ void ListBoxX::SetFont(Font &font) {
 			// On GTK < 3.21.0 the units are incorrectly parsed, so a font size in points
 			// need to use the "px" unit.  Normally we only get fonts in points here, so
 			// don't bother to handle the case the font is actually in pixels on < 3.21.0.
-			if (gtk_check_version(3, 21, 0) != NULL || // on < 3.21.0
+			if (gtk_check_version(3, 21, 0) != nullptr || // on < 3.21.0
 			    pango_font_description_get_size_is_absolute(pfd)) {
 				ssFontSetting << "px; ";
 			} else {
@@ -1505,7 +1516,7 @@ void ListBoxX::SetFont(Font &font) {
 			ssFontSetting << "font-weight:"<< pango_font_description_get_weight(pfd) << "; ";
 			ssFontSetting << "}";
 			gtk_css_provider_load_from_data(GTK_CSS_PROVIDER(cssProvider),
-				ssFontSetting.str().c_str(), -1, NULL);
+				ssFontSetting.str().c_str(), -1, nullptr);
 		}
 #else
 		gtk_widget_modify_font(PWidget(list), PFont(font)->pfd);
@@ -1543,7 +1554,7 @@ PRectangle ListBoxX::GetDesiredRect() {
 		// This, apparently unnecessary call, ensures gtk_tree_view_column_cell_get_size
 		// returns reasonable values.
 #if GTK_CHECK_VERSION(3,0,0)
-		gtk_widget_get_preferred_size(GTK_WIDGET(frame), NULL, &req);
+		gtk_widget_get_preferred_size(GTK_WIDGET(frame), nullptr, &req);
 #else
 		gtk_widget_size_request(GTK_WIDGET(frame), &req);
 #endif
@@ -1552,7 +1563,7 @@ PRectangle ListBoxX::GetDesiredRect() {
 		// First calculate height of the clist for our desired visible
 		// row count otherwise it tries to expand to the total # of rows
 		// Get cell height
-		int row_height = GetRowHeight();
+		const int row_height = GetRowHeight();
 #if GTK_CHECK_VERSION(3,0,0)
 		GtkStyleContext *styleContextFrame = gtk_widget_get_style_context(PWidget(frame));
 		GtkStateFlags stateFlagsFrame = gtk_style_context_get_state(styleContextFrame);
@@ -1573,7 +1584,7 @@ PRectangle ListBoxX::GetDesiredRect() {
 		gtk_style_context_get_border(styleContextFrameBorder, stateFlagsFrame, &border_border);
 		g_object_unref(styleContextFrameBorder);
 #	else // < 3.20
-		if (gtk_check_version(3, 20, 0) == NULL) {
+		if (gtk_check_version(3, 20, 0) == nullptr) {
 			// default to 1px all around as it's likely what it is, and so we don't miss 2px height
 			// on GTK 3.20 when built against an earlier version.
 			border_border.top = border_border.bottom = border_border.left = border_border.right = 1;
@@ -1599,7 +1610,7 @@ PRectangle ListBoxX::GetDesiredRect() {
 		// Add horizontal padding and borders
 		int horizontal_separator=0;
 		gtk_widget_style_get(PWidget(list),
-			"horizontal-separator", &horizontal_separator, NULL);
+			"horizontal-separator", &horizontal_separator, nullptr);
 		rc.right += horizontal_separator;
 #if GTK_CHECK_VERSION(3,0,0)
 		rc.right += (padding.left + padding.right
@@ -1615,7 +1626,7 @@ PRectangle ListBoxX::GetDesiredRect() {
 			GtkWidget *vscrollbar =
 				gtk_scrolled_window_get_vscrollbar(GTK_SCROLLED_WINDOW(scroller));
 #if GTK_CHECK_VERSION(3,0,0)
-			gtk_widget_get_preferred_size(vscrollbar, NULL, &req);
+			gtk_widget_get_preferred_size(vscrollbar, nullptr, &req);
 #else
 			gtk_widget_size_request(vscrollbar, &req);
 #endif
@@ -1651,32 +1662,32 @@ static void init_pixmap(ListImage *list_image) {
                                                          list_image->rgba_data->GetWidth(),
                                                          list_image->rgba_data->GetHeight(),
                                                          list_image->rgba_data->GetWidth() * 4,
-                                                         NULL,
-                                                         NULL);
+                                                         nullptr,
+                                                         nullptr);
 	}
 }
 
 #define SPACING 5
 
 void ListBoxX::Append(char *s, int type) {
-	ListImage *list_image = NULL;
+	ListImage *list_image = nullptr;
 	if ((type >= 0) && pixhash) {
-		list_image = static_cast<ListImage *>(g_hash_table_lookup((GHashTable *) pixhash
-		             , (gconstpointer) GINT_TO_POINTER(type)));
+		list_image = static_cast<ListImage *>(g_hash_table_lookup((GHashTable *) pixhash,
+						      GINT_TO_POINTER(type)));
 	}
 	GtkTreeIter iter;
 	GtkListStore *store =
 		GTK_LIST_STORE(gtk_tree_view_get_model(GTK_TREE_VIEW(list)));
 	gtk_list_store_append(GTK_LIST_STORE(store), &iter);
 	if (list_image) {
-		if (NULL == list_image->pixbuf)
+		if (nullptr == list_image->pixbuf)
 			init_pixmap(list_image);
 		if (list_image->pixbuf) {
 			gtk_list_store_set(GTK_LIST_STORE(store), &iter,
 								PIXBUF_COLUMN, list_image->pixbuf,
 								TEXT_COLUMN, s, -1);
 
-			gint pixbuf_width = gdk_pixbuf_get_width(list_image->pixbuf);
+			const gint pixbuf_width = gdk_pixbuf_get_width(list_image->pixbuf);
 			gint renderer_height, renderer_width;
 			gtk_cell_renderer_get_fixed_size(pixbuf_renderer,
 								&renderer_width, &renderer_height);
@@ -1691,7 +1702,7 @@ void ListBoxX::Append(char *s, int type) {
 			gtk_list_store_set(GTK_LIST_STORE(store), &iter,
 								TEXT_COLUMN, s, -1);
 	}
-	size_t len = strlen(s);
+	const size_t len = strlen(s);
 	if (maxItemCharacters < len)
 		maxItemCharacters = len;
 }
@@ -1699,7 +1710,7 @@ void ListBoxX::Append(char *s, int type) {
 int ListBoxX::Length() {
 	if (wid)
 		return gtk_tree_model_iter_n_children(gtk_tree_view_get_model
-											   (GTK_TREE_VIEW(list)), NULL);
+											   (GTK_TREE_VIEW(list)), nullptr);
 	return 0;
 }
 
@@ -1714,12 +1725,12 @@ void ListBoxX::Select(int n) {
 		return;
 	}
 
-	bool valid = gtk_tree_model_iter_nth_child(model, &iter, NULL, n) != FALSE;
+	const bool valid = gtk_tree_model_iter_nth_child(model, &iter, nullptr, n) != FALSE;
 	if (valid) {
 		gtk_tree_selection_select_iter(selection, &iter);
 
 		// Move the scrollbar to show the selection.
-		int total = Length();
+		const int total = Length();
 #if GTK_CHECK_VERSION(3,0,0)
 		GtkAdjustment *adj =
 			gtk_scrollable_get_vadjustment(GTK_SCROLLABLE(list));
@@ -1727,10 +1738,10 @@ void ListBoxX::Select(int n) {
 		GtkAdjustment *adj =
 			gtk_tree_view_get_vadjustment(GTK_TREE_VIEW(list));
 #endif
-		gfloat value = ((gfloat)n / total) * (gtk_adjustment_get_upper(adj) - gtk_adjustment_get_lower(adj))
+		gfloat value = (static_cast<gfloat>(n) / total) * (gtk_adjustment_get_upper(adj) - gtk_adjustment_get_lower(adj))
 							+ gtk_adjustment_get_lower(adj) - gtk_adjustment_get_page_size(adj) / 2;
 		// Get cell height
-		int row_height = GetRowHeight();
+		const int row_height = GetRowHeight();
 
 		int rows = Length();
 		if ((rows == 0) || (rows > desiredVisibleRows))
@@ -1738,7 +1749,7 @@ void ListBoxX::Select(int n) {
 		if (rows & 0x1) {
 			// Odd rows to display -- We are now in the middle.
 			// Align it so that we don't chop off rows.
-			value += (gfloat)row_height / 2.0;
+			value += static_cast<gfloat>(row_height) / 2.0f;
 		}
 		// Clamp it.
 		value = (value < 0)? 0 : value;
@@ -1765,7 +1776,7 @@ int ListBoxX::GetSelection() {
 	selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(list));
 	if (gtk_tree_selection_get_selected(selection, &model, &iter)) {
 		GtkTreePath *path = gtk_tree_model_get_path(model, &iter);
-		int *indices = gtk_tree_path_get_indices(path);
+		const int *indices = gtk_tree_path_get_indices(path);
 		// Don't free indices.
 		if (indices)
 			index = indices[0];
@@ -1780,7 +1791,7 @@ int ListBoxX::Find(const char *prefix) {
 		gtk_tree_view_get_model(GTK_TREE_VIEW(list));
 	bool valid = gtk_tree_model_get_iter_first(model, &iter) != FALSE;
 	int i = 0;
-	while(valid) {
+	while (valid) {
 		gchar *s;
 		gtk_tree_model_get(model, &iter, TEXT_COLUMN, &s, -1);
 		if (s && (0 == strncmp(prefix, s, strlen(prefix)))) {
@@ -1795,10 +1806,10 @@ int ListBoxX::Find(const char *prefix) {
 }
 
 void ListBoxX::GetValue(int n, char *value, int len) {
-	char *text = NULL;
+	char *text = nullptr;
 	GtkTreeIter iter;
 	GtkTreeModel *model = gtk_tree_view_get_model(GTK_TREE_VIEW(list));
-	bool valid = gtk_tree_model_iter_nth_child(model, &iter, NULL, n) != FALSE;
+	const bool valid = gtk_tree_model_iter_nth_child(model, &iter, nullptr, n) != FALSE;
 	if (valid) {
 		gtk_tree_model_get(model, &iter, TEXT_COLUMN, &text, -1);
 	}
@@ -1822,12 +1833,12 @@ void ListBoxX::RegisterRGBA(int type, RGBAImage *image) {
 		pixhash = g_hash_table_new(g_direct_hash, g_direct_equal);
 	}
 	ListImage *list_image = static_cast<ListImage *>(g_hash_table_lookup((GHashTable *) pixhash,
-		(gconstpointer) GINT_TO_POINTER(type)));
+				GINT_TO_POINTER(type)));
 	if (list_image) {
 		// Drop icon already registered
 		if (list_image->pixbuf)
 			g_object_unref(list_image->pixbuf);
-		list_image->pixbuf = NULL;
+		list_image->pixbuf = nullptr;
 		list_image->rgba_data = image;
 	} else {
 		list_image = g_new0(ListImage, 1);
@@ -1857,10 +1868,10 @@ void ListBoxX::SetDelegate(IListBoxDelegate *lbDelegate) {
 
 void ListBoxX::SetList(const char *listText, char separator, char typesep) {
 	Clear();
-	int count = strlen(listText) + 1;
+	const size_t count = strlen(listText) + 1;
 	std::vector<char> words(listText, listText+count);
 	char *startword = &words[0];
-	char *numword = NULL;
+	char *numword = nullptr;
 	int i = 0;
 	for (; words[i]; i++) {
 		if (words[i] == separator) {
@@ -1869,7 +1880,7 @@ void ListBoxX::SetList(const char *listText, char separator, char typesep) {
 				*numword = '\0';
 			Append(startword, numword?atoi(numword + 1):-1);
 			startword = &words[0] + i + 1;
-			numword = NULL;
+			numword = nullptr;
 		} else if (words[i] == typesep) {
 			numword = &words[0] + i;
 		}
@@ -1881,7 +1892,7 @@ void ListBoxX::SetList(const char *listText, char separator, char typesep) {
 	}
 }
 
-Menu::Menu() noexcept : mid(0) {}
+Menu::Menu() noexcept : mid(nullptr) {}
 
 void Menu::CreatePopUp() {
 	Destroy();
@@ -1892,7 +1903,7 @@ void Menu::CreatePopUp() {
 void Menu::Destroy() {
 	if (mid)
 		g_object_unref(G_OBJECT(mid));
-	mid = 0;
+	mid = nullptr;
 }
 
 #if !GTK_CHECK_VERSION(3,22,0)
@@ -1908,12 +1919,12 @@ void Menu::Show(Point pt, Window &w) {
 	gtk_widget_show_all(GTK_WIDGET(widget));
 #if GTK_CHECK_VERSION(3,22,0)
 	// Rely on GTK+ to do the right thing with positioning
-	gtk_menu_popup_at_pointer(widget, NULL);
+	gtk_menu_popup_at_pointer(widget, nullptr);
 #else
-	GdkRectangle rcMonitor = MonitorRectangleForWidget(PWidget(w.GetID()));
+	const GdkRectangle rcMonitor = MonitorRectangleForWidget(PWidget(w.GetID()));
 	GtkRequisition requisition;
 #if GTK_CHECK_VERSION(3,0,0)
-	gtk_widget_get_preferred_size(GTK_WIDGET(widget), NULL, &requisition);
+	gtk_widget_get_preferred_size(GTK_WIDGET(widget), nullptr, &requisition);
 #else
 	gtk_widget_size_request(GTK_WIDGET(widget), &requisition);
 #endif
@@ -1923,7 +1934,7 @@ void Menu::Show(Point pt, Window &w) {
 	if ((pt.y + requisition.height) > rcMonitor.y + rcMonitor.height) {
 		pt.y = rcMonitor.y + rcMonitor.height - requisition.height;
 	}
-	gtk_menu_popup(widget, NULL, NULL, MenuPositionFunc,
+	gtk_menu_popup(widget, nullptr, nullptr, MenuPositionFunc,
 		GINT_TO_POINTER((static_cast<int>(pt.y) << 16) | static_cast<int>(pt.x)), 0,
 		gtk_get_current_event_time());
 #endif
@@ -1931,38 +1942,38 @@ void Menu::Show(Point pt, Window &w) {
 
 class DynamicLibraryImpl : public DynamicLibrary {
 protected:
-	GModule* m;
+	GModule *m;
 public:
-	explicit DynamicLibraryImpl(const char *modulePath) {
+	explicit DynamicLibraryImpl(const char *modulePath) noexcept {
 		m = g_module_open(modulePath, G_MODULE_BIND_LAZY);
 	}
 
 	~DynamicLibraryImpl() override {
-		if (m != NULL)
+		if (m != nullptr)
 			g_module_close(m);
 	}
 
 	// Use g_module_symbol to get a pointer to the relevant function.
 	Function FindFunction(const char *name) override {
-		if (m != NULL) {
-			gpointer fn_address = NULL;
-			gboolean status = g_module_symbol(m, name, &fn_address);
+		if (m != nullptr) {
+			gpointer fn_address = nullptr;
+			const gboolean status = g_module_symbol(m, name, &fn_address);
 			if (status)
 				return static_cast<Function>(fn_address);
 			else
-				return NULL;
+				return nullptr;
 		} else {
-			return NULL;
+			return nullptr;
 		}
 	}
 
 	bool IsValid() override {
-		return m != NULL;
+		return m != nullptr;
 	}
 };
 
 DynamicLibrary *DynamicLibrary::Load(const char *modulePath) {
-	return static_cast<DynamicLibrary *>( new DynamicLibraryImpl(modulePath) );
+	return static_cast<DynamicLibrary *>(new DynamicLibraryImpl(modulePath));
 }
 
 ColourDesired Platform::Chrome() {
@@ -2017,7 +2028,7 @@ void Platform::DebugPrintf(const char *, ...) {}
 static bool assertionPopUps = true;
 
 bool Platform::ShowAssertionPopUps(bool assertionPopUps_) {
-	bool ret = assertionPopUps;
+	const bool ret = assertionPopUps;
 	assertionPopUps = assertionPopUps_;
 	return ret;
 }
diff --git a/scintilla/gtk/ScintillaGTK.cxx b/scintilla/gtk/ScintillaGTK.cxx
index 2deac8c75c..a78f00d7ba 100644
--- a/scintilla/gtk/ScintillaGTK.cxx
+++ b/scintilla/gtk/ScintillaGTK.cxx
@@ -7,7 +7,6 @@
 #include <cstdlib>
 #include <cassert>
 #include <cstring>
-#include <cctype>
 #include <cstdio>
 #include <ctime>
 #include <cmath>
@@ -29,7 +28,10 @@
 #include <gdk/gdkwayland.h>
 #endif
 
-#if defined(__WIN32__) || defined(_MSC_VER)
+#if defined(_WIN32)
+// On Win32 use windows.h to access clipboard (rectangular format) and systems parameters
+#undef NOMINMAX
+#define NOMINMAX
 #include <windows.h>
 #endif
 
@@ -43,6 +45,7 @@
 #include "SciLexer.h"
 #endif
 #include "StringCopy.h"
+#include "CharacterCategory.h"
 #ifdef SCI_LEXER
 #include "LexerModule.h"
 #endif
@@ -92,7 +95,7 @@
 #define SC_INDICATOR_CONVERTED INDIC_IME+2
 #define SC_INDICATOR_UNKNOWN INDIC_IME_MAX
 
-static GdkWindow *WindowFromWidget(GtkWidget *w) {
+static GdkWindow *WindowFromWidget(GtkWidget *w) noexcept {
 	return gtk_widget_get_window(w);
 }
 
@@ -105,7 +108,7 @@ static GdkWindow *WindowFromWidget(GtkWidget *w) {
 
 using namespace Scintilla;
 
-static GdkWindow *PWindow(const Window &w) {
+static GdkWindow *PWindow(const Window &w) noexcept {
 	GtkWidget *widget = static_cast<GtkWidget *>(w.GetID());
 	return gtk_widget_get_window(widget);
 }
@@ -113,26 +116,25 @@ static GdkWindow *PWindow(const Window &w) {
 extern std::string UTF8FromLatin1(const char *s, int len);
 
 enum {
-    COMMAND_SIGNAL,
-    NOTIFY_SIGNAL,
-    LAST_SIGNAL
+	COMMAND_SIGNAL,
+	NOTIFY_SIGNAL,
+	LAST_SIGNAL
 };
 
 static gint scintilla_signals[LAST_SIGNAL] = { 0 };
 
 enum {
-    TARGET_STRING,
-    TARGET_TEXT,
-    TARGET_COMPOUND_TEXT,
-    TARGET_UTF8_STRING,
-    TARGET_URI
+	TARGET_STRING,
+	TARGET_TEXT,
+	TARGET_COMPOUND_TEXT,
+	TARGET_UTF8_STRING,
+	TARGET_URI
 };
 
-GdkAtom ScintillaGTK::atomClipboard = 0;
-GdkAtom ScintillaGTK::atomUTF8 = 0;
-GdkAtom ScintillaGTK::atomString = 0;
-GdkAtom ScintillaGTK::atomUriList = 0;
-GdkAtom ScintillaGTK::atomDROPFILES_DND = 0;
+GdkAtom ScintillaGTK::atomUTF8 = nullptr;
+GdkAtom ScintillaGTK::atomString = nullptr;
+GdkAtom ScintillaGTK::atomUriList = nullptr;
+GdkAtom ScintillaGTK::atomDROPFILES_DND = nullptr;
 
 static const GtkTargetEntry clipboardCopyTargets[] = {
 	{ (gchar *) "UTF8_STRING", 0, TARGET_UTF8_STRING },
@@ -149,7 +151,7 @@ static const gint nClipboardPasteTargets = ELEMENTS(clipboardPasteTargets);
 
 static const GdkDragAction actionCopyOrMove = static_cast<GdkDragAction>(GDK_ACTION_COPY | GDK_ACTION_MOVE);
 
-static GtkWidget *PWidget(Window &w) {
+static GtkWidget *PWidget(const Window &w) noexcept {
 	return static_cast<GtkWidget *>(w.GetID());
 }
 
@@ -159,20 +161,25 @@ ScintillaGTK *ScintillaGTK::FromWidget(GtkWidget *widget) {
 }
 
 ScintillaGTK::ScintillaGTK(_ScintillaObject *sci_) :
-		adjustmentv(0), adjustmenth(0),
-		verticalScrollBarWidth(30), horizontalScrollBarHeight(30),
-		evbtn(nullptr), capturedMouse(false), dragWasDropped(false),
-		lastKey(0), rectangularSelectionModifier(SCMOD_CTRL), parentClass(0),
-		im_context(NULL), lastNonCommonScript(PANGO_SCRIPT_INVALID_CODE),
-		lastWheelMouseDirection(0),
-		wheelMouseIntensity(0),
-		smoothScrollY(0),
-		smoothScrollX(0),
-		rgnUpdate(0),
-		repaintFullWindow(false),
-		styleIdleID(0),
-		accessibilityEnabled(SC_ACCESSIBILITY_ENABLED),
-		accessible(0) {
+	adjustmentv(nullptr), adjustmenth(nullptr),
+	verticalScrollBarWidth(30), horizontalScrollBarHeight(30),
+	evbtn(nullptr),
+	buttonMouse(0),
+	capturedMouse(false), dragWasDropped(false),
+	lastKey(0), rectangularSelectionModifier(SCMOD_CTRL),
+	parentClass(nullptr),
+	atomSought(nullptr),
+	im_context(nullptr),
+	lastNonCommonScript(PANGO_SCRIPT_INVALID_CODE),
+	lastWheelMouseDirection(0),
+	wheelMouseIntensity(0),
+	smoothScrollY(0),
+	smoothScrollX(0),
+	rgnUpdate(nullptr),
+	repaintFullWindow(false),
+	styleIdleID(0),
+	accessibilityEnabled(SC_ACCESSIBILITY_ENABLED),
+	accessible(nullptr) {
 	sci = sci_;
 	wMain = GTK_WIDGET(sci);
 
@@ -182,7 +189,7 @@ ScintillaGTK::ScintillaGTK(_ScintillaObject *sci_) :
 	// There does not seem to be a real standard for indicating that the clipboard
 	// contains a rectangular selection, so copy Developer Studio.
 	cfColumnSelect = static_cast<CLIPFORMAT>(
-		::RegisterClipboardFormat("MSDEVColumnSelect"));
+				 ::RegisterClipboardFormat("MSDEVColumnSelect"));
 
 	// Get intellimouse parameters when running on win32; otherwise use
 	// reasonable default
@@ -241,7 +248,7 @@ void ScintillaGTK::RealizeThis(GtkWidget *widget) {
 	attrs.cursor = cursor;
 #if GTK_CHECK_VERSION(3,0,0)
 	gtk_widget_set_window(widget, gdk_window_new(gtk_widget_get_parent_window(widget), &attrs,
-		GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_CURSOR));
+			      GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_CURSOR));
 #if GTK_CHECK_VERSION(3,8,0)
 	gtk_widget_register_window(widget, gtk_widget_get_window(widget));
 #else
@@ -249,13 +256,13 @@ void ScintillaGTK::RealizeThis(GtkWidget *widget) {
 #endif
 #if !GTK_CHECK_VERSION(3,18,0)
 	gtk_style_context_set_background(gtk_widget_get_style_context(widget),
-		gtk_widget_get_window(widget));
+					 gtk_widget_get_window(widget));
 #endif
 	gdk_window_show(gtk_widget_get_window(widget));
 	UnRefCursor(cursor);
 #else
 	widget->window = gdk_window_new(gtk_widget_get_parent_window(widget), &attrs,
-		GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP | GDK_WA_CURSOR);
+					GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP | GDK_WA_CURSOR);
 	gdk_window_set_user_data(widget->window, widget);
 	widget->style = gtk_style_attach(widget->style, widget->window);
 	gdk_window_set_background(widget->window, &widget->style->bg[GTK_STATE_NORMAL]);
@@ -267,15 +274,15 @@ void ScintillaGTK::RealizeThis(GtkWidget *widget) {
 
 	im_context = gtk_im_multicontext_new();
 	g_signal_connect(G_OBJECT(im_context), "commit",
-		G_CALLBACK(Commit), this);
+			 G_CALLBACK(Commit), this);
 	g_signal_connect(G_OBJECT(im_context), "preedit_changed",
-		G_CALLBACK(PreeditChanged), this);
+			 G_CALLBACK(PreeditChanged), this);
 	gtk_im_context_set_client_window(im_context, WindowFromWidget(widget));
 	GtkWidget *widtxt = PWidget(wText);	//	// No code inside the G_OBJECT macro
 	g_signal_connect_after(G_OBJECT(widtxt), "style_set",
-		G_CALLBACK(ScintillaGTK::StyleSetText), NULL);
+			       G_CALLBACK(ScintillaGTK::StyleSetText), nullptr);
 	g_signal_connect_after(G_OBJECT(widtxt), "realize",
-		G_CALLBACK(ScintillaGTK::RealizeText), NULL);
+			       G_CALLBACK(ScintillaGTK::RealizeText), nullptr);
 	gtk_widget_realize(widtxt);
 	gtk_widget_realize(PWidget(scrollbarv));
 	gtk_widget_realize(PWidget(scrollbarh));
@@ -296,7 +303,7 @@ void ScintillaGTK::RealizeThis(GtkWidget *widget) {
 	g_signal_connect(PWidget(wSelection), "selection_get", G_CALLBACK(PrimarySelection), (gpointer) this);
 	g_signal_connect(PWidget(wSelection), "selection_clear_event", G_CALLBACK(PrimaryClear), (gpointer) this);
 	gtk_selection_add_targets(PWidget(wSelection), GDK_SELECTION_PRIMARY,
-	                          clipboardCopyTargets, nClipboardCopyTargets);
+				  clipboardCopyTargets, nClipboardCopyTargets);
 }
 
 void ScintillaGTK::Realize(GtkWidget *widget) {
@@ -321,7 +328,7 @@ void ScintillaGTK::UnRealizeThis(GtkWidget *widget) {
 		gtk_widget_unrealize(PWidget(wPreedit));
 		gtk_widget_unrealize(PWidget(wPreeditDraw));
 		g_object_unref(im_context);
-		im_context = NULL;
+		im_context = nullptr;
 		if (GTK_WIDGET_CLASS(parentClass)->unrealize)
 			GTK_WIDGET_CLASS(parentClass)->unrealize(widget);
 
@@ -338,8 +345,8 @@ void ScintillaGTK::UnRealize(GtkWidget *widget) {
 
 static void MapWidget(GtkWidget *widget) {
 	if (widget &&
-	        gtk_widget_get_visible(GTK_WIDGET(widget)) &&
-	        !IS_WIDGET_MAPPED(widget)) {
+			gtk_widget_get_visible(GTK_WIDGET(widget)) &&
+			!IS_WIDGET_MAPPED(widget)) {
 		gtk_widget_map(widget);
 	}
 }
@@ -389,11 +396,11 @@ void ScintillaGTK::UnMap(GtkWidget *widget) {
 
 void ScintillaGTK::ForAll(GtkCallback callback, gpointer callback_data) {
 	try {
-		(*callback) (PWidget(wText), callback_data);
+		(*callback)(PWidget(wText), callback_data);
 		if (PWidget(scrollbarv))
-			(*callback) (PWidget(scrollbarv), callback_data);
+			(*callback)(PWidget(scrollbarv), callback_data);
 		if (PWidget(scrollbarh))
-			(*callback) (PWidget(scrollbarh), callback_data);
+			(*callback)(PWidget(scrollbarh), callback_data);
 	} catch (...) {
 		errorStatus = SC_STATUS_FAILURE;
 	}
@@ -402,7 +409,7 @@ void ScintillaGTK::ForAll(GtkCallback callback, gpointer callback_data) {
 void ScintillaGTK::MainForAll(GtkContainer *container, gboolean include_internals, GtkCallback callback, gpointer callback_data) {
 	ScintillaGTK *sciThis = FromWidget((GtkWidget *)container);
 
-	if (callback != NULL && include_internals) {
+	if (callback && include_internals) {
 		sciThis->ForAll(callback, callback_data);
 	}
 }
@@ -421,7 +428,7 @@ class PreEditString {
 
 	explicit PreEditString(GtkIMContext *im_context) {
 		gtk_im_context_get_preedit_string(im_context, &str, &attrs, &cursor_pos);
-		validUTF8 = g_utf8_validate(str, strlen(str), NULL);
+		validUTF8 = g_utf8_validate(str, strlen(str), nullptr);
 		uniStr = g_utf8_to_ucs4_fast(str, strlen(str), &uniStrLen);
 		pscript = pango_script_for_unichar(uniStr[0]);
 	}
@@ -437,9 +444,9 @@ class PreEditString {
 gint ScintillaGTK::FocusInThis(GtkWidget *) {
 	try {
 		SetFocusState(true);
-		if (im_context != NULL) {
+		if (im_context) {
 			PreEditString pes(im_context);
-			if (PWidget(wPreedit) != NULL) {
+			if (PWidget(wPreedit)) {
 				if (strlen(pes.str) > 0) {
 					gtk_widget_show(PWidget(wPreedit));
 				} else {
@@ -464,9 +471,9 @@ gint ScintillaGTK::FocusOutThis(GtkWidget *) {
 	try {
 		SetFocusState(false);
 
-		if (PWidget(wPreedit) != NULL)
+		if (PWidget(wPreedit))
 			gtk_widget_hide(PWidget(wPreedit));
-		if (im_context != NULL)
+		if (im_context)
 			gtk_im_context_focus_out(im_context);
 
 	} catch (...) {
@@ -486,8 +493,8 @@ void ScintillaGTK::SizeRequest(GtkWidget *widget, GtkRequisition *requisition) {
 	requisition->height = 1;
 	GtkRequisition child_requisition;
 #if GTK_CHECK_VERSION(3,0,0)
-	gtk_widget_get_preferred_size(PWidget(sciThis->scrollbarh), NULL, &child_requisition);
-	gtk_widget_get_preferred_size(PWidget(sciThis->scrollbarv), NULL, &child_requisition);
+	gtk_widget_get_preferred_size(PWidget(sciThis->scrollbarh), nullptr, &child_requisition);
+	gtk_widget_get_preferred_size(PWidget(sciThis->scrollbarv), nullptr, &child_requisition);
 #else
 	gtk_widget_size_request(PWidget(sciThis->scrollbarh), &child_requisition);
 	gtk_widget_size_request(PWidget(sciThis->scrollbarv), &child_requisition);
@@ -516,10 +523,10 @@ void ScintillaGTK::SizeAllocate(GtkWidget *widget, GtkAllocation *allocation) {
 		gtk_widget_set_allocation(widget, allocation);
 		if (IS_WIDGET_REALIZED(widget))
 			gdk_window_move_resize(WindowFromWidget(widget),
-			        allocation->x,
-			        allocation->y,
-			        allocation->width,
-			        allocation->height);
+					       allocation->x,
+					       allocation->y,
+					       allocation->width,
+					       allocation->height);
 
 		sciThis->Resize(allocation->width, allocation->height);
 
@@ -530,7 +537,7 @@ void ScintillaGTK::SizeAllocate(GtkWidget *widget, GtkAllocation *allocation) {
 
 void ScintillaGTK::Init() {
 	parentClass = reinterpret_cast<GtkWidgetClass *>(
-	                  g_type_class_ref(gtk_container_get_type()));
+			      g_type_class_ref(gtk_container_get_type()));
 
 	gint maskSmooth = 0;
 #if defined(GDK_WINDOWING_WAYLAND)
@@ -544,18 +551,18 @@ void ScintillaGTK::Init() {
 	gtk_widget_set_can_focus(PWidget(wMain), TRUE);
 	gtk_widget_set_sensitive(PWidget(wMain), TRUE);
 	gtk_widget_set_events(PWidget(wMain),
-	                      GDK_EXPOSURE_MASK
-	                      | GDK_SCROLL_MASK
-	                      | maskSmooth
-	                      | GDK_STRUCTURE_MASK
-	                      | GDK_KEY_PRESS_MASK
-	                      | GDK_KEY_RELEASE_MASK
-	                      | GDK_FOCUS_CHANGE_MASK
-	                      | GDK_LEAVE_NOTIFY_MASK
-	                      | GDK_BUTTON_PRESS_MASK
-	                      | GDK_BUTTON_RELEASE_MASK
-	                      | GDK_POINTER_MOTION_MASK
-	                      | GDK_POINTER_MOTION_HINT_MASK);
+			      GDK_EXPOSURE_MASK
+			      | GDK_SCROLL_MASK
+			      | maskSmooth
+			      | GDK_STRUCTURE_MASK
+			      | GDK_KEY_PRESS_MASK
+			      | GDK_KEY_RELEASE_MASK
+			      | GDK_FOCUS_CHANGE_MASK
+			      | GDK_LEAVE_NOTIFY_MASK
+			      | GDK_BUTTON_PRESS_MASK
+			      | GDK_BUTTON_RELEASE_MASK
+			      | GDK_POINTER_MOTION_MASK
+			      | GDK_POINTER_MOTION_HINT_MASK);
 
 	wText = gtk_drawing_area_new();
 	gtk_widget_set_parent(PWidget(wText), PWidget(wMain));
@@ -563,15 +570,15 @@ void ScintillaGTK::Init() {
 	gtk_widget_show(widtxt);
 #if GTK_CHECK_VERSION(3,0,0)
 	g_signal_connect(G_OBJECT(widtxt), "draw",
-			   G_CALLBACK(ScintillaGTK::DrawText), this);
+			 G_CALLBACK(ScintillaGTK::DrawText), this);
 #else
 	g_signal_connect(G_OBJECT(widtxt), "expose_event",
-			   G_CALLBACK(ScintillaGTK::ExposeText), this);
+			 G_CALLBACK(ScintillaGTK::ExposeText), this);
 #endif
 #if GTK_CHECK_VERSION(3,0,0)
 	// we need a runtime check because we don't want double buffering when
 	// running on >= 3.9.2
-	if (gtk_check_version(3,9,2) != NULL /* on < 3.9.2 */)
+	if (gtk_check_version(3, 9, 2) != nullptr /* on < 3.9.2 */)
 #endif
 	{
 #if !GTK_CHECK_VERSION(3,14,0)
@@ -589,7 +596,7 @@ void ScintillaGTK::Init() {
 #endif
 	gtk_widget_set_can_focus(PWidget(scrollbarv), FALSE);
 	g_signal_connect(G_OBJECT(adjustmentv), "value_changed",
-			   G_CALLBACK(ScrollSignal), this);
+			 G_CALLBACK(ScrollSignal), this);
 	gtk_widget_set_parent(PWidget(scrollbarv), PWidget(wMain));
 	gtk_widget_show(PWidget(scrollbarv));
 
@@ -601,15 +608,15 @@ void ScintillaGTK::Init() {
 #endif
 	gtk_widget_set_can_focus(PWidget(scrollbarh), FALSE);
 	g_signal_connect(G_OBJECT(adjustmenth), "value_changed",
-			   G_CALLBACK(ScrollHSignal), this);
+			 G_CALLBACK(ScrollHSignal), this);
 	gtk_widget_set_parent(PWidget(scrollbarh), PWidget(wMain));
 	gtk_widget_show(PWidget(scrollbarh));
 
 	gtk_widget_grab_focus(PWidget(wMain));
 
 	gtk_drag_dest_set(GTK_WIDGET(PWidget(wMain)),
-	                  GTK_DEST_DEFAULT_ALL, clipboardPasteTargets, nClipboardPasteTargets,
-	                  actionCopyOrMove);
+			  GTK_DEST_DEFAULT_ALL, clipboardPasteTargets, nClipboardPasteTargets,
+			  actionCopyOrMove);
 
 	/* create pre-edit window */
 	wPreedit = gtk_window_new(GTK_WINDOW_POPUP);
@@ -617,10 +624,10 @@ void ScintillaGTK::Init() {
 	GtkWidget *predrw = PWidget(wPreeditDraw);      // No code inside the G_OBJECT macro
 #if GTK_CHECK_VERSION(3,0,0)
 	g_signal_connect(G_OBJECT(predrw), "draw",
-		G_CALLBACK(DrawPreedit), this);
+			 G_CALLBACK(DrawPreedit), this);
 #else
 	g_signal_connect(G_OBJECT(predrw), "expose_event",
-		G_CALLBACK(ExposePreedit), this);
+			 G_CALLBACK(ExposePreedit), this);
 #endif
 	gtk_container_add(GTK_CONTAINER(PWidget(wPreedit)), predrw);
 	gtk_widget_show(predrw);
@@ -630,15 +637,15 @@ void ScintillaGTK::Init() {
 	if (g_object_class_find_property(G_OBJECT_GET_CLASS(
 			G_OBJECT(gtk_settings_get_default())), "gtk-cursor-blink")) {
 		g_object_get(G_OBJECT(
-			gtk_settings_get_default()), "gtk-cursor-blink", &blinkOn, NULL);
+				     gtk_settings_get_default()), "gtk-cursor-blink", &blinkOn, nullptr);
 	}
 	if (blinkOn &&
-		g_object_class_find_property(G_OBJECT_GET_CLASS(
-			G_OBJECT(gtk_settings_get_default())), "gtk-cursor-blink-time")) {
+			g_object_class_find_property(G_OBJECT_GET_CLASS(
+						G_OBJECT(gtk_settings_get_default())), "gtk-cursor-blink-time")) {
 		gint value;
 		g_object_get(G_OBJECT(
-			gtk_settings_get_default()), "gtk-cursor-blink-time", &value, NULL);
-		caret.period = gint(value / 1.75);
+				     gtk_settings_get_default()), "gtk-cursor-blink-time", &value, nullptr);
+		caret.period = static_cast<int>(value / 1.75);
 	} else {
 		caret.period = 0;
 	}
@@ -658,9 +665,9 @@ void ScintillaGTK::Finalise() {
 		FineTickerCancel(tr);
 	}
 	if (accessible) {
-		gtk_accessible_set_widget(GTK_ACCESSIBLE(accessible), NULL);
+		gtk_accessible_set_widget(GTK_ACCESSIBLE(accessible), nullptr);
 		g_object_unref(accessible);
-		accessible = 0;
+		accessible = nullptr;
 	}
 
 	ScintillaBase::Finalise();
@@ -682,7 +689,7 @@ void ScintillaGTK::DisplayCursor(Window::Cursor c) {
 
 bool ScintillaGTK::DragThreshold(Point ptStart, Point ptNow) {
 	return gtk_drag_check_threshold(GTK_WIDGET(PWidget(wMain)),
-		ptStart.x, ptStart.y, ptNow.x, ptNow.y);
+					ptStart.x, ptStart.y, ptNow.x, ptNow.y);
 }
 
 void ScintillaGTK::StartDrag() {
@@ -692,23 +699,23 @@ void ScintillaGTK::StartDrag() {
 	GtkTargetList *tl = gtk_target_list_new(clipboardCopyTargets, nClipboardCopyTargets);
 #if GTK_CHECK_VERSION(3,10,0)
 	gtk_drag_begin_with_coordinates(GTK_WIDGET(PWidget(wMain)),
-	               tl,
-	               actionCopyOrMove,
-	               buttonMouse,
-	               evbtn,
-			-1, -1);
+					tl,
+					actionCopyOrMove,
+					buttonMouse,
+					evbtn,
+					-1, -1);
 #else
 	gtk_drag_begin(GTK_WIDGET(PWidget(wMain)),
-	               tl,
-	               actionCopyOrMove,
-	               buttonMouse,
-	               evbtn);
+		       tl,
+		       actionCopyOrMove,
+		       buttonMouse,
+		       evbtn);
 #endif
 }
 
 namespace Scintilla {
 std::string ConvertText(const char *s, size_t len, const char *charSetDest,
-	const char *charSetSource, bool transliterations, bool silent) {
+			const char *charSetSource, bool transliterations, bool silent) {
 	// s is not const because of different versions of iconv disagreeing about const
 	std::string destForm;
 	Converter conv(charSetDest, charSetSource, transliterations);
@@ -720,7 +727,7 @@ std::string ConvertText(const char *s, size_t len, const char *charSetDest,
 		gsize inLeft = len;
 		char *putf = &destForm[0];
 		char *pout = putf;
-		gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
+		const gsize conversions = conv.Convert(&pin, &inLeft, &pout, &outLeft);
 		if (conversions == sizeFailure) {
 			if (!silent) {
 				if (len == 1)
@@ -744,7 +751,7 @@ std::string ConvertText(const char *s, size_t len, const char *charSetDest,
 // Returns the target converted to UTF8.
 // Return the length in bytes.
 Sci::Position ScintillaGTK::TargetAsUTF8(char *text) const {
-	Sci::Position targetLength = targetEnd - targetStart;
+	const Sci::Position targetLength = targetEnd - targetStart;
 	if (IsUnicodeMode()) {
 		if (text) {
 			pdoc->GetCharRange(text, targetStart, targetLength);
@@ -771,7 +778,7 @@ Sci::Position ScintillaGTK::TargetAsUTF8(char *text) const {
 // Translates a nul terminated UTF8 string into the document encoding.
 // Return the length of the result in bytes.
 Sci::Position ScintillaGTK::EncodedFromUTF8(const char *utf8, char *encoded) const {
-	Sci::Position inputLength = (lengthForEncode >= 0) ? lengthForEncode : strlen(utf8);
+	const Sci::Position inputLength = (lengthForEncode >= 0) ? lengthForEncode : strlen(utf8);
 	if (IsUnicodeMode()) {
 		if (encoded) {
 			memcpy(encoded, utf8, inputLength);
@@ -799,12 +806,12 @@ Sci::Position ScintillaGTK::EncodedFromUTF8(const char *utf8, char *encoded) con
 
 bool ScintillaGTK::ValidCodePage(int codePage) const {
 	return codePage == 0
-	|| codePage == SC_CP_UTF8
-	|| codePage == 932
-	|| codePage == 936
-	|| codePage == 949
-	|| codePage == 950
-	|| codePage == 1361;
+	       || codePage == SC_CP_UTF8
+	       || codePage == 932
+	       || codePage == 936
+	       || codePage == 949
+	       || codePage == 950
+	       || codePage == 1361;
 }
 
 sptr_t ScintillaGTK::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
@@ -831,7 +838,7 @@ sptr_t ScintillaGTK::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam
 
 		case SCI_ENCODEDFROMUTF8:
 			return EncodedFromUTF8(ConstCharPtrFromUPtr(wParam),
-			        CharPtrFromSPtr(lParam));
+					       CharPtrFromSPtr(lParam));
 
 		case SCI_SETRECTANGULARSELECTIONMODIFIER:
 			rectangularSelectionModifier = wParam;
@@ -841,15 +848,15 @@ sptr_t ScintillaGTK::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam
 			return rectangularSelectionModifier;
 
 		case SCI_SETREADONLY: {
-			sptr_t ret = ScintillaBase::WndProc(iMessage, wParam, lParam);
-			if (accessible) {
-				ScintillaGTKAccessible *sciAccessible = ScintillaGTKAccessible::FromAccessible(accessible);
-				if (sciAccessible) {
-					sciAccessible->NotifyReadOnly();
+				const sptr_t ret = ScintillaBase::WndProc(iMessage, wParam, lParam);
+				if (accessible) {
+					ScintillaGTKAccessible *sciAccessible = ScintillaGTKAccessible::FromAccessible(accessible);
+					if (sciAccessible) {
+						sciAccessible->NotifyReadOnly();
+					}
 				}
+				return ret;
 			}
-			return ret;
-		}
 
 		case SCI_GETACCESSIBILITY:
 			return accessibilityEnabled;
@@ -867,7 +874,7 @@ sptr_t ScintillaGTK::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam
 		default:
 			return ScintillaBase::WndProc(iMessage, wParam, lParam);
 		}
-	} catch (std::bad_alloc&) {
+	} catch (std::bad_alloc &) {
 		errorStatus = SC_STATUS_BADALLOC;
 	} catch (...) {
 		errorStatus = SC_STATUS_FAILURE;
@@ -901,7 +908,7 @@ bool ScintillaGTK::SetIdle(bool on) {
 		if (!idler.state) {
 			idler.state = true;
 			idler.idlerID = GUINT_TO_POINTER(
-				gdk_threads_add_idle_full(G_PRIORITY_DEFAULT_IDLE, IdleCallback, this, NULL));
+						gdk_threads_add_idle_full(G_PRIORITY_DEFAULT_IDLE, IdleCallback, this, nullptr));
 		}
 	} else {
 		// Stop idler, if it's running
@@ -959,11 +966,13 @@ bool ScintillaGTK::PaintContains(PRectangle rc) {
 		} else if (rgnUpdate) {
 #if GTK_CHECK_VERSION(3,0,0)
 			cairo_rectangle_t grc = {rc.left, rc.top,
-				rc.right - rc.left, rc.bottom - rc.top};
+						 rc.right - rc.left, rc.bottom - rc.top
+						};
 			contains = CRectListContains(rgnUpdate, grc);
 #else
 			GdkRectangle grc = {static_cast<gint>(rc.left), static_cast<gint>(rc.top),
-				static_cast<gint>(rc.right - rc.left), static_cast<gint>(rc.bottom - rc.top)};
+					    static_cast<gint>(rc.right - rc.left), static_cast<gint>(rc.bottom - rc.top)
+					   };
 			if (gdk_region_rect_in(rgnUpdate, &grc) != GDK_OVERLAP_RECTANGLE_IN) {
 				contains = false;
 			}
@@ -1023,35 +1032,35 @@ void ScintillaGTK::SetHorizontalScrollPos() {
 
 bool ScintillaGTK::ModifyScrollBars(Sci::Line nMax, Sci::Line nPage) {
 	bool modified = false;
-	int pageScroll = LinesToScroll();
+	const int pageScroll = LinesToScroll();
 
 	if (gtk_adjustment_get_upper(adjustmentv) != (nMax + 1) ||
-	        gtk_adjustment_get_page_size(adjustmentv) != nPage ||
-	        gtk_adjustment_get_page_increment(adjustmentv) != pageScroll) {
+			gtk_adjustment_get_page_size(adjustmentv) != nPage ||
+			gtk_adjustment_get_page_increment(adjustmentv) != pageScroll) {
 		gtk_adjustment_set_upper(adjustmentv, nMax + 1);
-	        gtk_adjustment_set_page_size(adjustmentv, nPage);
-	        gtk_adjustment_set_page_increment(adjustmentv, pageScroll);
+		gtk_adjustment_set_page_size(adjustmentv, nPage);
+		gtk_adjustment_set_page_increment(adjustmentv, pageScroll);
 #if !GTK_CHECK_VERSION(3,18,0)
 		gtk_adjustment_changed(GTK_ADJUSTMENT(adjustmentv));
 #endif
 		modified = true;
 	}
 
-	PRectangle rcText = GetTextRectangle();
+	const PRectangle rcText = GetTextRectangle();
 	int horizEndPreferred = scrollWidth;
 	if (horizEndPreferred < 0)
 		horizEndPreferred = 0;
-	unsigned int pageWidth = rcText.Width();
-	unsigned int pageIncrement = pageWidth / 3;
-	unsigned int charWidth = vs.styles[STYLE_DEFAULT].aveCharWidth;
+	const unsigned int pageWidth = static_cast<unsigned int>(rcText.Width());
+	const unsigned int pageIncrement = pageWidth / 3;
+	const unsigned int charWidth = vs.styles[STYLE_DEFAULT].aveCharWidth;
 	if (gtk_adjustment_get_upper(adjustmenth) != horizEndPreferred ||
-	        gtk_adjustment_get_page_size(adjustmenth) != pageWidth ||
-	        gtk_adjustment_get_page_increment(adjustmenth) != pageIncrement ||
-	        gtk_adjustment_get_step_increment(adjustmenth) != charWidth) {
+			gtk_adjustment_get_page_size(adjustmenth) != pageWidth ||
+			gtk_adjustment_get_page_increment(adjustmenth) != pageIncrement ||
+			gtk_adjustment_get_step_increment(adjustmenth) != charWidth) {
 		gtk_adjustment_set_upper(adjustmenth, horizEndPreferred);
-	        gtk_adjustment_set_page_size(adjustmenth, pageWidth);
-	        gtk_adjustment_set_page_increment(adjustmenth, pageIncrement);
-	        gtk_adjustment_set_step_increment(adjustmenth, charWidth);
+		gtk_adjustment_set_page_size(adjustmenth, pageWidth);
+		gtk_adjustment_set_page_increment(adjustmenth, pageIncrement);
+		gtk_adjustment_set_step_increment(adjustmenth, charWidth);
 #if !GTK_CHECK_VERSION(3,18,0)
 		gtk_adjustment_changed(GTK_ADJUSTMENT(adjustmenth));
 #endif
@@ -1065,20 +1074,20 @@ bool ScintillaGTK::ModifyScrollBars(Sci::Line nMax, Sci::Line nPage) {
 }
 
 void ScintillaGTK::ReconfigureScrollBars() {
-	PRectangle rc = wMain.GetClientPosition();
-	Resize(rc.Width(), rc.Height());
+	const PRectangle rc = wMain.GetClientPosition();
+	Resize(static_cast<int>(rc.Width()), static_cast<int>(rc.Height()));
 }
 
 void ScintillaGTK::NotifyChange() {
 	g_signal_emit(G_OBJECT(sci), scintilla_signals[COMMAND_SIGNAL], 0,
-	                Platform::LongFromTwoShorts(GetCtrlID(), SCEN_CHANGE), PWidget(wMain));
+		      Platform::LongFromTwoShorts(GetCtrlID(), SCEN_CHANGE), PWidget(wMain));
 }
 
 void ScintillaGTK::NotifyFocus(bool focus) {
 	if (commandEvents)
 		g_signal_emit(G_OBJECT(sci), scintilla_signals[COMMAND_SIGNAL], 0,
-				Platform::LongFromTwoShorts
-						(GetCtrlID(), focus ? SCEN_SETFOCUS : SCEN_KILLFOCUS), PWidget(wMain));
+			      Platform::LongFromTwoShorts
+			      (GetCtrlID(), focus ? SCEN_SETFOCUS : SCEN_KILLFOCUS), PWidget(wMain));
 	Editor::NotifyFocus(focus);
 }
 
@@ -1086,7 +1095,7 @@ void ScintillaGTK::NotifyParent(SCNotification scn) {
 	scn.nmhdr.hwndFrom = PWidget(wMain);
 	scn.nmhdr.idFrom = GetCtrlID();
 	g_signal_emit(G_OBJECT(sci), scintilla_signals[NOTIFY_SIGNAL], 0,
-	                GetCtrlID(), &scn);
+		      GetCtrlID(), &scn);
 }
 
 void ScintillaGTK::NotifyKey(int key, int modifiers) {
@@ -1124,7 +1133,7 @@ class CaseFolderDBCS : public CaseFolderTable {
 			return 1;
 		} else if (*charSet) {
 			std::string sUTF8 = ConvertText(mixed, lenMixed,
-				"UTF-8", charSet, false);
+							"UTF-8", charSet, false);
 			if (!sUTF8.empty()) {
 				gchar *mapped = g_utf8_casefold(sUTF8.c_str(), sUTF8.length());
 				size_t lenMapped = strlen(mapped);
@@ -1159,12 +1168,12 @@ CaseFolder *ScintillaGTK::CaseFolderForEncoding() {
 					sCharacter[0] = i;
 					// Silent as some bytes have no assigned character
 					std::string sUTF8 = ConvertText(sCharacter, 1,
-						"UTF-8", charSetBuffer, false, true);
+									"UTF-8", charSetBuffer, false, true);
 					if (!sUTF8.empty()) {
 						gchar *mapped = g_utf8_casefold(sUTF8.c_str(), sUTF8.length());
 						if (mapped) {
 							std::string mappedBack = ConvertText(mapped, strlen(mapped),
-								charSetBuffer, "UTF-8", false, true);
+											     charSetBuffer, "UTF-8", false, true);
 							if ((mappedBack.length() == 1) && (mappedBack[0] != sCharacter[0])) {
 								pcf->SetTranslation(sCharacter[0], mappedBack[0]);
 							}
@@ -1177,7 +1186,7 @@ CaseFolder *ScintillaGTK::CaseFolderForEncoding() {
 				return new CaseFolderDBCS(charSetBuffer);
 			}
 		}
-		return 0;
+		return nullptr;
 	}
 }
 
@@ -1205,8 +1214,8 @@ std::string ScintillaGTK::CaseMapString(const std::string &s, int caseMapping) {
 
 	if (IsUnicodeMode()) {
 		std::string retMapped(s.length() * maxExpansionCaseConversion, 0);
-		size_t lenMapped = CaseConvertString(&retMapped[0], retMapped.length(), s.c_str(), s.length(),
-			(caseMapping == cmUpper) ? CaseConversionUpper : CaseConversionLower);
+		const size_t lenMapped = CaseConvertString(&retMapped[0], retMapped.length(), s.c_str(), s.length(),
+					 (caseMapping == cmUpper) ? CaseConversionUpper : CaseConversionLower);
 		retMapped.resize(lenMapped);
 		return retMapped;
 	}
@@ -1219,7 +1228,7 @@ std::string ScintillaGTK::CaseMapString(const std::string &s, int caseMapping) {
 	} else {
 		// Change text to UTF-8
 		std::string sUTF8 = ConvertText(s.c_str(), s.length(),
-			"UTF-8", charSetBuffer, false);
+						"UTF-8", charSetBuffer, false);
 		CaseMapper mapper(sUTF8, caseMapping == cmUpper);
 		return ConvertText(mapper.mapped, strlen(mapper.mapped), charSetBuffer, "UTF-8", false);
 	}
@@ -1252,37 +1261,47 @@ void ScintillaGTK::Copy() {
 	}
 }
 
-void ScintillaGTK::Paste() {
-	atomSought = atomUTF8;
-	GtkClipboard *clipBoard =
-		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), atomClipboard);
-	if (clipBoard == NULL)
-		return;
+namespace {
 
-	// helper class for the asynchronous paste not to risk calling in a destroyed ScintillaGTK
-	class Helper : GObjectWatcher {
-		ScintillaGTK *sci;
+// Helper class for the asynchronous paste not to risk calling in a destroyed ScintillaGTK
 
-		void Destroyed() override {
-			sci = 0;
-		}
+class SelectionReceiver : GObjectWatcher {
+	ScintillaGTK *sci;
 
-	public:
-		Helper(ScintillaGTK *sci_) :
-				GObjectWatcher(G_OBJECT(PWidget(sci_->wMain))),
-				sci(sci_) {
-		}
+	void Destroyed() override {
+		sci = nullptr;
+	}
 
-		static void ClipboardReceived(GtkClipboard *, GtkSelectionData *selection_data, gpointer data) {
-			Helper *self = static_cast<Helper*>(data);
-			if (self->sci != 0) {
-				self->sci->ReceivedSelection(selection_data);
-			}
-			delete self;
+public:
+	SelectionReceiver(ScintillaGTK *sci_) :
+		GObjectWatcher(G_OBJECT(sci_->MainObject())),
+		sci(sci_) {
+	}
+
+	static void ClipboardReceived(GtkClipboard *, GtkSelectionData *selection_data, gpointer data) {
+		SelectionReceiver *self = static_cast<SelectionReceiver *>(data);
+		if (self->sci) {
+			self->sci->ReceivedClipboard(selection_data);
 		}
-	};
+		delete self;
+	}
+};
 
-	gtk_clipboard_request_contents(clipBoard, atomSought, Helper::ClipboardReceived, new Helper(this));
+}
+
+void ScintillaGTK::RequestSelection(GdkAtom atomSelection) {
+	atomSought = atomUTF8;
+	GtkClipboard *clipBoard =
+		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), atomSelection);
+	if (clipBoard) {
+		gtk_clipboard_request_contents(clipBoard, atomSought,
+					       SelectionReceiver::ClipboardReceived,
+					       new SelectionReceiver(this));
+	}
+}
+
+void ScintillaGTK::Paste() {
+	RequestSelection(GDK_SELECTION_CLIPBOARD);
 }
 
 void ScintillaGTK::CreateCallTipWindow(PRectangle rc) {
@@ -1293,23 +1312,25 @@ void ScintillaGTK::CreateCallTipWindow(PRectangle rc) {
 		gtk_container_add(GTK_CONTAINER(PWidget(ct.wCallTip)), widcdrw);
 #if GTK_CHECK_VERSION(3,0,0)
 		g_signal_connect(G_OBJECT(widcdrw), "draw",
-				   G_CALLBACK(ScintillaGTK::DrawCT), &ct);
+				 G_CALLBACK(ScintillaGTK::DrawCT), &ct);
 #else
 		g_signal_connect(G_OBJECT(widcdrw), "expose_event",
-				   G_CALLBACK(ScintillaGTK::ExposeCT), &ct);
+				 G_CALLBACK(ScintillaGTK::ExposeCT), &ct);
 #endif
 		g_signal_connect(G_OBJECT(widcdrw), "button_press_event",
-				   G_CALLBACK(ScintillaGTK::PressCT), this);
+				 G_CALLBACK(ScintillaGTK::PressCT), this);
 		gtk_widget_set_events(widcdrw,
-			GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK);
+				      GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK);
 		GtkWidget *top = gtk_widget_get_toplevel(static_cast<GtkWidget *>(wMain.GetID()));
 		gtk_window_set_transient_for(GTK_WINDOW(static_cast<GtkWidget *>(PWidget(ct.wCallTip))),
-			GTK_WINDOW(top));
+					     GTK_WINDOW(top));
 	}
-	gtk_widget_set_size_request(PWidget(ct.wDraw), rc.Width(), rc.Height());
+	const int width = static_cast<int>(rc.Width());
+	const int height = static_cast<int>(rc.Height());
+	gtk_widget_set_size_request(PWidget(ct.wDraw), width, height);
 	ct.wDraw.Show();
 	if (PWindow(ct.wCallTip)) {
-		gdk_window_resize(PWindow(ct.wCallTip), rc.Width(), rc.Height());
+		gdk_window_resize(PWindow(ct.wCallTip), width, height);
 	}
 }
 
@@ -1321,7 +1342,7 @@ void ScintillaGTK::AddToPopUp(const char *label, int cmd, bool enabled) {
 		menuItem = gtk_separator_menu_item_new();
 	gtk_menu_shell_append(GTK_MENU_SHELL(popup.GetID()), menuItem);
 	g_object_set_data(G_OBJECT(menuItem), "CmdNum", GINT_TO_POINTER(cmd));
-	g_signal_connect(G_OBJECT(menuItem),"activate", G_CALLBACK(PopUpCB), this);
+	g_signal_connect(G_OBJECT(menuItem), "activate", G_CALLBACK(PopUpCB), this);
 
 	if (cmd) {
 		if (menuItem)
@@ -1332,7 +1353,7 @@ void ScintillaGTK::AddToPopUp(const char *label, int cmd, bool enabled) {
 bool ScintillaGTK::OwnPrimarySelection() {
 	return (wSelection.Created() &&
 		(gdk_selection_owner_get(GDK_SELECTION_PRIMARY) == PWindow(wSelection)) &&
-		(PWindow(wSelection) != NULL));
+		(PWindow(wSelection) != nullptr));
 }
 
 void ScintillaGTK::ClaimSelection() {
@@ -1341,12 +1362,12 @@ void ScintillaGTK::ClaimSelection() {
 	if (!sel.Empty() && wSelection.Created() && IS_WIDGET_REALIZED(GTK_WIDGET(PWidget(wSelection)))) {
 		primarySelection = true;
 		gtk_selection_owner_set(GTK_WIDGET(PWidget(wSelection)),
-		                        GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME);
+					GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME);
 		primary.Clear();
 	} else if (OwnPrimarySelection()) {
 		primarySelection = true;
 		if (primary.Empty())
-			gtk_selection_owner_set(NULL, GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME);
+			gtk_selection_owner_set(nullptr, GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME);
 	} else {
 		primarySelection = false;
 		primary.Clear();
@@ -1396,7 +1417,7 @@ void ScintillaGTK::GetGtkSelectionText(GtkSelectionData *selectionData, Selectio
 		} else {
 			// Assume buffer is in same encoding as selection
 			selText.Copy(dest, pdoc->dbcsCodePage,
-				vs.styles[STYLE_DEFAULT].characterSet, isRectangular, false);
+				     vs.styles[STYLE_DEFAULT].characterSet, isRectangular, false);
 		}
 	} else {	// UTF-8
 		const char *charSetBuffer = CharacterSetID();
@@ -1404,39 +1425,59 @@ void ScintillaGTK::GetGtkSelectionText(GtkSelectionData *selectionData, Selectio
 			// Convert to locale
 			dest = ConvertText(dest.c_str(), dest.length(), charSetBuffer, "UTF-8", true);
 			selText.Copy(dest, pdoc->dbcsCodePage,
-				vs.styles[STYLE_DEFAULT].characterSet, isRectangular, false);
+				     vs.styles[STYLE_DEFAULT].characterSet, isRectangular, false);
 		} else {
 			selText.Copy(dest, SC_CP_UTF8, 0, isRectangular, false);
 		}
 	}
 }
 
+void ScintillaGTK::InsertSelection(GtkSelectionData *selectionData) {
+	const gint length = gtk_selection_data_get_length(selectionData);
+	if (length >= 0) {
+		GdkAtom selection = gtk_selection_data_get_selection(selectionData);
+		SelectionText selText;
+		GetGtkSelectionText(selectionData, selText);
+
+		UndoGroup ug(pdoc);
+		if (selection == GDK_SELECTION_CLIPBOARD) {
+			ClearSelection(multiPasteMode == SC_MULTIPASTE_EACH);
+		}
+
+		InsertPasteShape(selText.Data(), selText.Length(),
+				 selText.rectangular ? pasteRectangular : pasteStream);
+		EnsureCaretVisible();
+	}
+	Redraw();
+}
+
+GObject *ScintillaGTK::MainObject() const noexcept {
+	return G_OBJECT(PWidget(wMain));
+}
+
+void ScintillaGTK::ReceivedClipboard(GtkSelectionData *selection_data) noexcept {
+	try {
+		InsertSelection(selection_data);
+	} catch (...) {
+		errorStatus = SC_STATUS_FAILURE;
+	}
+}
+
 void ScintillaGTK::ReceivedSelection(GtkSelectionData *selection_data) {
 	try {
-		if ((SelectionOfGSD(selection_data) == atomClipboard) ||
-		        (SelectionOfGSD(selection_data) == GDK_SELECTION_PRIMARY)) {
+		if ((SelectionOfGSD(selection_data) == GDK_SELECTION_CLIPBOARD) ||
+				(SelectionOfGSD(selection_data) == GDK_SELECTION_PRIMARY)) {
 			if ((atomSought == atomUTF8) && (LengthOfGSD(selection_data) <= 0)) {
 				atomSought = atomString;
 				gtk_selection_convert(GTK_WIDGET(PWidget(wMain)),
-				        SelectionOfGSD(selection_data), atomSought, GDK_CURRENT_TIME);
+						      SelectionOfGSD(selection_data), atomSought, GDK_CURRENT_TIME);
 			} else if ((LengthOfGSD(selection_data) > 0) &&
-			        ((TypeOfGSD(selection_data) == GDK_TARGET_STRING) || (TypeOfGSD(selection_data) == atomUTF8))) {
-				SelectionText selText;
-				GetGtkSelectionText(selection_data, selText);
-
-				UndoGroup ug(pdoc);
-				if (SelectionOfGSD(selection_data) != GDK_SELECTION_PRIMARY) {
-					ClearSelection(multiPasteMode == SC_MULTIPASTE_EACH);
-				}
-
-				InsertPasteShape(selText.Data(), selText.Length(),
-					selText.rectangular ? pasteRectangular : pasteStream);
-				EnsureCaretVisible();
+					((TypeOfGSD(selection_data) == GDK_TARGET_STRING) || (TypeOfGSD(selection_data) == atomUTF8))) {
+				InsertSelection(selection_data);
 			}
 		}
 //	else fprintf(stderr, "Target non string %d %d\n", (int)(selection_data->type),
 //		(int)(atomUTF8));
-		Redraw();
 	} catch (...) {
 		errorStatus = SC_STATUS_FAILURE;
 	}
@@ -1507,29 +1548,29 @@ void ScintillaGTK::GetSelection(GtkSelectionData *selection_data, guint info, Se
 		gtk_selection_data_set_text(selection_data, textData, len);
 	} else {
 		gtk_selection_data_set(selection_data,
-			static_cast<GdkAtom>(GDK_SELECTION_TYPE_STRING),
-			8, reinterpret_cast<const guchar *>(textData), len);
+				       static_cast<GdkAtom>(GDK_SELECTION_TYPE_STRING),
+				       8, reinterpret_cast<const guchar *>(textData), len);
 	}
 }
 
 void ScintillaGTK::StoreOnClipboard(SelectionText *clipText) {
 	GtkClipboard *clipBoard =
-		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), atomClipboard);
-	if (clipBoard == NULL) // Occurs if widget isn't in a toplevel
+		gtk_widget_get_clipboard(GTK_WIDGET(PWidget(wMain)), GDK_SELECTION_CLIPBOARD);
+	if (clipBoard == nullptr) // Occurs if widget isn't in a toplevel
 		return;
 
 	if (gtk_clipboard_set_with_data(clipBoard, clipboardCopyTargets, nClipboardCopyTargets,
-				    ClipboardGetSelection, ClipboardClearSelection, clipText)) {
+					ClipboardGetSelection, ClipboardClearSelection, clipText)) {
 		gtk_clipboard_set_can_store(clipBoard, clipboardCopyTargets, nClipboardCopyTargets);
 	}
 }
 
 void ScintillaGTK::ClipboardGetSelection(GtkClipboard *, GtkSelectionData *selection_data, guint info, void *data) {
-	GetSelection(selection_data, info, static_cast<SelectionText*>(data));
+	GetSelection(selection_data, info, static_cast<SelectionText *>(data));
 }
 
 void ScintillaGTK::ClipboardClearSelection(GtkClipboard *, void *data) {
-	SelectionText *obj = static_cast<SelectionText*>(data);
+	SelectionText *obj = static_cast<SelectionText *>(data);
 	delete obj;
 }
 
@@ -1595,9 +1636,9 @@ void ScintillaGTK::Resize(int width, int height) {
 
 	// These allocations should never produce negative sizes as they would wrap around to huge
 	// unsigned numbers inside GTK+ causing warnings.
-	bool showSBHorizontal = horizontalScrollBarVisible && !Wrapping();
+	const bool showSBHorizontal = horizontalScrollBarVisible && !Wrapping();
 
-	GtkAllocation alloc;
+	GtkAllocation alloc = {};
 	if (showSBHorizontal) {
 		gtk_widget_show(GTK_WIDGET(PWidget(scrollbarh)));
 		alloc.x = 0;
@@ -1632,7 +1673,7 @@ void ScintillaGTK::Resize(int width, int height) {
 #if GTK_CHECK_VERSION(3, 0, 0)
 	// please GTK 3.20 and ask wText what size it wants, although we know it doesn't really need
 	// anything special as it's ours.
-	gtk_widget_get_preferred_size(PWidget(wText), &requisition, NULL);
+	gtk_widget_get_preferred_size(PWidget(wText), &requisition, nullptr);
 	alloc.width = requisition.width;
 	alloc.height = requisition.height;
 #endif
@@ -1641,10 +1682,12 @@ void ScintillaGTK::Resize(int width, int height) {
 	gtk_widget_size_allocate(GTK_WIDGET(PWidget(wText)), &alloc);
 }
 
-static void SetAdjustmentValue(GtkAdjustment *object, int value) {
+namespace {
+
+void SetAdjustmentValue(GtkAdjustment *object, int value) {
 	GtkAdjustment *adjustment = GTK_ADJUSTMENT(object);
-	int maxValue = static_cast<int>(
-		gtk_adjustment_get_upper(adjustment) - gtk_adjustment_get_page_size(adjustment));
+	const int maxValue = static_cast<int>(
+				     gtk_adjustment_get_upper(adjustment) - gtk_adjustment_get_page_size(adjustment));
 
 	if (value > maxValue)
 		value = maxValue;
@@ -1653,21 +1696,29 @@ static void SetAdjustmentValue(GtkAdjustment *object, int value) {
 	gtk_adjustment_set_value(adjustment, value);
 }
 
-static int modifierTranslated(int sciModifier) {
+int modifierTranslated(int sciModifier) noexcept {
 	switch (sciModifier) {
-		case SCMOD_SHIFT:
-			return GDK_SHIFT_MASK;
-		case SCMOD_CTRL:
-			return GDK_CONTROL_MASK;
-		case SCMOD_ALT:
-			return GDK_MOD1_MASK;
-		case SCMOD_SUPER:
-			return GDK_MOD4_MASK;
-		default:
-			return 0;
+	case SCMOD_SHIFT:
+		return GDK_SHIFT_MASK;
+	case SCMOD_CTRL:
+		return GDK_CONTROL_MASK;
+	case SCMOD_ALT:
+		return GDK_MOD1_MASK;
+	case SCMOD_SUPER:
+		return GDK_MOD4_MASK;
+	default:
+		return 0;
 	}
 }
 
+Point PointOfEvent(const GdkEventButton *event) noexcept {
+	// Use floor as want to round in the same direction (-infinity) so
+	// there is no stickiness crossing 0.0.
+	return Point(static_cast<XYPOSITION>(std::floor(event->x)), static_cast<XYPOSITION>(std::floor(event->y)));
+}
+
+}
+
 gint ScintillaGTK::PressThis(GdkEventButton *event) {
 	try {
 		//Platform::DebugPrintf("Press %x time=%d state = %x button = %x\n",this,event->time, event->state, event->button);
@@ -1680,10 +1731,8 @@ gint ScintillaGTK::PressThis(GdkEventButton *event) {
 		}
 		evbtn = gdk_event_copy(reinterpret_cast<GdkEvent *>(event));
 		buttonMouse = event->button;
-		Point pt;
-		pt.x = floor(event->x);
-		pt.y = floor(event->y);
-		PRectangle rcClient = GetClientRectangle();
+		const Point pt = PointOfEvent(event);
+		const PRectangle rcClient = GetClientRectangle();
 		//Platform::DebugPrintf("Press %0d,%0d in %0d,%0d %0d,%0d\n",
 		//	pt.x, pt.y, rcClient.left, rcClient.top, rcClient.right, rcClient.bottom);
 		if ((pt.x > rcClient.right) || (pt.y > rcClient.bottom)) {
@@ -1691,35 +1740,33 @@ gint ScintillaGTK::PressThis(GdkEventButton *event) {
 			return FALSE;
 		}
 
-		bool shift = (event->state & GDK_SHIFT_MASK) != 0;
+		const bool shift = (event->state & GDK_SHIFT_MASK) != 0;
 		bool ctrl = (event->state & GDK_CONTROL_MASK) != 0;
 		// On X, instead of sending literal modifiers use the user specified
 		// modifier, defaulting to control instead of alt.
 		// This is because most X window managers grab alt + click for moving
-		bool alt = (event->state & modifierTranslated(rectangularSelectionModifier)) != 0;
+		const bool alt = (event->state & modifierTranslated(rectangularSelectionModifier)) != 0;
 
 		gtk_widget_grab_focus(PWidget(wMain));
 		if (event->button == 1) {
 #if PLAT_GTK_MACOSX
-			bool meta = ctrl;
+			const bool meta = ctrl;
 			// GDK reports the Command modifer key as GDK_MOD2_MASK for button events,
 			// not GDK_META_MASK like in key events.
 			ctrl = (event->state & GDK_MOD2_MASK) != 0;
 #else
-			bool meta = false;
+			const bool meta = false;
 #endif
 			ButtonDownWithModifiers(pt, event->time, ModifierFlags(shift, ctrl, alt, meta));
 		} else if (event->button == 2) {
 			// Grab the primary selection if it exists
-			SelectionPosition pos = SPositionFromLocation(pt, false, false, UserVirtualSpace());
+			const SelectionPosition pos = SPositionFromLocation(pt, false, false, UserVirtualSpace());
 			if (OwnPrimarySelection() && primary.Empty())
 				CopySelectionRange(&primary);
 
 			sel.Clear();
 			SetSelection(pos, pos);
-			atomSought = atomUTF8;
-			gtk_selection_convert(GTK_WIDGET(PWidget(wMain)), GDK_SELECTION_PRIMARY,
-			        atomSought, event->time);
+			RequestSelection(GDK_SELECTION_PRIMARY);
 		} else if (event->button == 3) {
 			if (!PointInSelection(pt))
 				SetEmptySelection(PositionFromLocation(pt));
@@ -1732,12 +1779,12 @@ gint ScintillaGTK::PressThis(GdkEventButton *event) {
 				ContextMenu(Point(pt.x + ox, pt.y + oy));
 			} else {
 #if PLAT_GTK_MACOSX
-				bool meta = ctrl;
+				const bool meta = ctrl;
 				// GDK reports the Command modifer key as GDK_MOD2_MASK for button events,
 				// not GDK_META_MASK like in key events.
 				ctrl = (event->state & GDK_MOD2_MASK) != 0;
 #else
-				bool meta = false;
+				const bool meta = false;
 #endif
 				RightButtonDownWithModifiers(pt, event->time, ModifierFlags(shift, ctrl, alt, meta));
 				return FALSE;
@@ -1775,9 +1822,7 @@ gint ScintillaGTK::MouseRelease(GtkWidget *widget, GdkEventButton *event) {
 		if (!sciThis->HaveMouseCapture())
 			return FALSE;
 		if (event->button == 1) {
-			Point pt;
-			pt.x = int(event->x);
-			pt.y = int(event->y);
+			Point pt = PointOfEvent(event);
 			//Platform::DebugPrintf("Up %x %x %d %d %d\n",
 			//	sciThis,event->window,event->time, pt.x, pt.y);
 			if (event->window != PWindow(sciThis->wMain))
@@ -1785,9 +1830,9 @@ gint ScintillaGTK::MouseRelease(GtkWidget *widget, GdkEventButton *event) {
 				// scrollbar, not the drawing window so just repeat the most recent point.
 				pt = sciThis->ptMouseLast;
 			const int modifiers = ModifierFlags(
-				(event->state & GDK_SHIFT_MASK) != 0,
-				(event->state & GDK_CONTROL_MASK) != 0,
-				(event->state & modifierTranslated(sciThis->rectangularSelectionModifier)) != 0);
+						      (event->state & GDK_SHIFT_MASK) != 0,
+						      (event->state & GDK_CONTROL_MASK) != 0,
+						      (event->state & modifierTranslated(sciThis->rectangularSelectionModifier)) != 0);
 			sciThis->ButtonUpWithModifiers(pt, event->time, modifiers);
 		}
 	} catch (...) {
@@ -1802,7 +1847,7 @@ gint ScintillaGTK::ScrollEvent(GtkWidget *widget, GdkEventScroll *event) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	try {
 
-		if (widget == NULL || event == NULL)
+		if (widget == nullptr || event == nullptr)
 			return FALSE;
 
 #if defined(GDK_WINDOWING_WAYLAND)
@@ -1811,12 +1856,12 @@ gint ScintillaGTK::ScrollEvent(GtkWidget *widget, GdkEventScroll *event) {
 			sciThis->smoothScrollY += event->delta_y * smoothScrollFactor;
 			sciThis->smoothScrollX += event->delta_x * smoothScrollFactor;;
 			if (ABS(sciThis->smoothScrollY) >= 1.0) {
-				const int scrollLines = trunc(sciThis->smoothScrollY);
+				const int scrollLines = std::trunc(sciThis->smoothScrollY);
 				sciThis->ScrollTo(sciThis->topLine + scrollLines);
 				sciThis->smoothScrollY -= scrollLines;
 			}
 			if (ABS(sciThis->smoothScrollX) >= 1.0) {
-				const int scrollPixels = trunc(sciThis->smoothScrollX);
+				const int scrollPixels = std::trunc(sciThis->smoothScrollX);
 				sciThis->HorizontalScrollTo(sciThis->xOffset + scrollPixels);
 				sciThis->smoothScrollX -= scrollPixels;
 			}
@@ -1913,7 +1958,7 @@ gint ScintillaGTK::Motion(GtkWidget *widget, GdkEventMotion *event) {
 		if (event->is_hint) {
 #if GTK_CHECK_VERSION(3,0,0)
 			gdk_window_get_device_position(event->window,
-				event->device, &x, &y, &state);
+						       event->device, &x, &y, &state);
 #else
 			gdk_window_get_pointer(event->window, &x, &y, &state);
 #endif
@@ -1924,11 +1969,11 @@ gint ScintillaGTK::Motion(GtkWidget *widget, GdkEventMotion *event) {
 		}
 		//Platform::DebugPrintf("Move %x %x %d %c %d %d\n",
 		//	sciThis,event->window,event->time,event->is_hint? 'h' :'.', x, y);
-		Point pt(x, y);
+		const Point pt(static_cast<XYPOSITION>(x), static_cast<XYPOSITION>(y));
 		const int modifiers = ModifierFlags(
-				(event->state & GDK_SHIFT_MASK) != 0,
-				(event->state & GDK_CONTROL_MASK) != 0,
-				(event->state & modifierTranslated(sciThis->rectangularSelectionModifier)) != 0);
+					      (event->state & GDK_SHIFT_MASK) != 0,
+					      (event->state & GDK_CONTROL_MASK) != 0,
+					      (event->state & modifierTranslated(sciThis->rectangularSelectionModifier)) != 0);
 		sciThis->ButtonMoveWithModifiers(pt, event->time, modifiers);
 	} catch (...) {
 		sciThis->errorStatus = SC_STATUS_FAILURE;
@@ -2090,10 +2135,10 @@ gboolean ScintillaGTK::KeyThis(GdkEventKey *event) {
 			return true;
 		}
 
-		bool shift = (event->state & GDK_SHIFT_MASK) != 0;
+		const bool shift = (event->state & GDK_SHIFT_MASK) != 0;
 		bool ctrl = (event->state & GDK_CONTROL_MASK) != 0;
-		bool alt = (event->state & GDK_MOD1_MASK) != 0;
-		bool super = (event->state & GDK_MOD4_MASK) != 0;
+		const bool alt = (event->state & GDK_MOD1_MASK) != 0;
+		const bool super = (event->state & GDK_MOD4_MASK) != 0;
 		guint key = event->keyval;
 		if ((ctrl || alt) && (key < 128))
 			key = toupper(key);
@@ -2110,12 +2155,12 @@ gboolean ScintillaGTK::KeyThis(GdkEventKey *event) {
 
 		bool consumed = false;
 #if !(PLAT_GTK_MACOSX)
-		bool meta = false;
+		const bool meta = false;
 #else
-		bool meta = ctrl;
+		const bool meta = ctrl;
 		ctrl = (event->state & GDK_META_MASK) != 0;
 #endif
-		bool added = KeyDownWithModifiers(key, ModifierFlags(shift, ctrl, alt, meta, super), &consumed) != 0;
+		const bool added = KeyDownWithModifiers(key, ModifierFlags(shift, ctrl, alt, meta, super), &consumed) != 0;
 		if (!consumed)
 			consumed = added;
 		//fprintf(stderr, "SK-key: %d %x %x\n",event->keyval, event->state, consumed);
@@ -2204,7 +2249,7 @@ bool ScintillaGTK::KoreanIME() {
 void ScintillaGTK::MoveImeCarets(int pos) {
 	// Move carets relatively by bytes
 	for (size_t r=0; r<sel.Count(); r++) {
-		int positionInsert = sel.Range(r).Start().Position();
+		const Sci::Position positionInsert = sel.Range(r).Start().Position();
 		sel.Range(r).caret.SetPosition(positionInsert + pos);
 		sel.Range(r).anchor.SetPosition(positionInsert + pos);
 	}
@@ -2220,7 +2265,7 @@ void ScintillaGTK::DrawImeIndicator(int indicator, int len) {
 	}
 	pdoc->DecorationSetCurrentIndicator(indicator);
 	for (size_t r=0; r<sel.Count(); r++) {
-		int positionInsert = sel.Range(r).Start().Position();
+		const Sci::Position positionInsert = sel.Range(r).Start().Position();
 		pdoc->DecorationFillRange(positionInsert - len, 1, len);
 	}
 }
@@ -2229,7 +2274,7 @@ static std::vector<int> MapImeIndicators(PangoAttrList *attrs, const char *u8Str
 	// Map input style to scintilla ime indicator.
 	// Attrs position points between UTF-8 bytes.
 	// Indicator index to be returned is character based though.
-	glong charactersLen = g_utf8_strlen(u8Str, strlen(u8Str));
+	const glong charactersLen = g_utf8_strlen(u8Str, strlen(u8Str));
 	std::vector<int> indicator(charactersLen, SC_INDICATOR_UNKNOWN);
 
 	PangoAttrIterator *iterunderline = pango_attr_list_get_iterator(attrs);
@@ -2237,9 +2282,9 @@ static std::vector<int> MapImeIndicators(PangoAttrList *attrs, const char *u8Str
 		do {
 			PangoAttribute  *attrunderline = pango_attr_iterator_get(iterunderline, PANGO_ATTR_UNDERLINE);
 			if (attrunderline) {
-				glong start = g_utf8_strlen(u8Str, attrunderline->start_index);
-				glong end = g_utf8_strlen(u8Str, attrunderline->end_index);
-				PangoUnderline uline = (PangoUnderline)((PangoAttrInt *)attrunderline)->value;
+				const glong start = g_utf8_strlen(u8Str, attrunderline->start_index);
+				const glong end = g_utf8_strlen(u8Str, attrunderline->end_index);
+				const PangoUnderline uline = (PangoUnderline)((PangoAttrInt *)attrunderline)->value;
 				for (glong i=start; i < end; ++i) {
 					switch (uline) {
 					case PANGO_UNDERLINE_NONE:
@@ -2262,10 +2307,10 @@ static std::vector<int> MapImeIndicators(PangoAttrList *attrs, const char *u8Str
 	PangoAttrIterator *itercolor = pango_attr_list_get_iterator(attrs);
 	if (itercolor) {
 		do {
-			PangoAttribute  *backcolor = pango_attr_iterator_get(itercolor, PANGO_ATTR_BACKGROUND);
+			const PangoAttribute *backcolor = pango_attr_iterator_get(itercolor, PANGO_ATTR_BACKGROUND);
 			if (backcolor) {
-				glong start = g_utf8_strlen(u8Str, backcolor->start_index);
-				glong end = g_utf8_strlen(u8Str, backcolor->end_index);
+				const glong start = g_utf8_strlen(u8Str, backcolor->start_index);
+				const glong end = g_utf8_strlen(u8Str, backcolor->end_index);
 				for (glong i=start; i < end; ++i) {
 					indicator[i] = SC_INDICATOR_TARGET;  // target converted
 				}
@@ -2278,10 +2323,10 @@ static std::vector<int> MapImeIndicators(PangoAttrList *attrs, const char *u8Str
 
 void ScintillaGTK::SetCandidateWindowPos() {
 	// Composition box accompanies candidate box.
-	Point pt = PointMainCaret();
+	const Point pt = PointMainCaret();
 	GdkRectangle imeBox = {0}; // No need to set width
-	imeBox.x = pt.x;           // Only need positiion
-	imeBox.y = pt.y + vs.lineHeight; // underneath the first charater
+	imeBox.x = static_cast<gint>(pt.x);           // Only need positiion
+	imeBox.y = static_cast<gint>(pt.y) + vs.lineHeight; // underneath the first charater
 	gtk_im_context_set_cursor_location(im_context, &imeBox);
 }
 
@@ -2300,7 +2345,7 @@ void ScintillaGTK::CommitThis(char *commitStr) {
 		gunichar *uniStr = g_utf8_to_ucs4_fast(commitStr, strlen(commitStr), &uniStrLen);
 		for (glong i = 0; i < uniStrLen; i++) {
 			gchar u8Char[UTF8MaxBytes+2] = {0};
-			gint u8CharLen = g_unichar_to_utf8(uniStr[i], u8Char);
+			const gint u8CharLen = g_unichar_to_utf8(uniStr[i], u8Char);
 			std::string docChar = u8Char;
 			if (!IsUnicodeMode())
 				docChar = ConvertText(u8Char, u8CharLen, charSetSource, "UTF-8", true);
@@ -2341,7 +2386,7 @@ void ScintillaGTK::PreeditChangedInlineThis() {
 		PreEditString preeditStr(im_context);
 		const char *charSetSource = CharacterSetID();
 
-		if (!preeditStr.validUTF8 || (charSetSource == NULL)) {
+		if (!preeditStr.validUTF8 || (charSetSource == nullptr)) {
 			ShowCaretAtCurrentPosition();
 			return;
 		}
@@ -2358,11 +2403,11 @@ void ScintillaGTK::PreeditChangedInlineThis() {
 
 		std::vector<int> indicator = MapImeIndicators(preeditStr.attrs, preeditStr.str);
 
-		bool tmpRecordingMacro = recordingMacro;
+		const bool tmpRecordingMacro = recordingMacro;
 		recordingMacro = false;
 		for (glong i = 0; i < preeditStr.uniStrLen; i++) {
 			gchar u8Char[UTF8MaxBytes+2] = {0};
-			gint u8CharLen = g_unichar_to_utf8(preeditStr.uniStr[i], u8Char);
+			const gint u8CharLen = g_unichar_to_utf8(preeditStr.uniStr[i], u8Char);
 			std::string docChar = u8Char;
 			if (!IsUnicodeMode())
 				docChar = ConvertText(u8Char, u8CharLen, charSetSource, "UTF-8", true);
@@ -2374,8 +2419,8 @@ void ScintillaGTK::PreeditChangedInlineThis() {
 		recordingMacro = tmpRecordingMacro;
 
 		// Move caret to ime cursor position.
-		int imeEndToImeCaretU32 = preeditStr.cursor_pos - preeditStr.uniStrLen;
-		int imeCaretPosDoc = pdoc->GetRelativePosition(CurrentPosition(), imeEndToImeCaretU32);
+		const int imeEndToImeCaretU32 = preeditStr.cursor_pos - preeditStr.uniStrLen;
+		const int imeCaretPosDoc = pdoc->GetRelativePosition(CurrentPosition(), imeEndToImeCaretU32);
 
 		MoveImeCarets(- CurrentPosition() + imeCaretPosDoc);
 
@@ -2437,19 +2482,19 @@ void ScintillaGTK::PreeditChanged(GtkIMContext *, ScintillaGTK *sciThis) {
 	}
 }
 
-void ScintillaGTK::StyleSetText(GtkWidget *widget, GtkStyle *, void*) {
-	RealizeText(widget, NULL);
+void ScintillaGTK::StyleSetText(GtkWidget *widget, GtkStyle *, void *) {
+	RealizeText(widget, nullptr);
 }
 
-void ScintillaGTK::RealizeText(GtkWidget *widget, void*) {
+void ScintillaGTK::RealizeText(GtkWidget *widget, void *) {
 	// Set NULL background to avoid automatic clearing so Scintilla responsible for all drawing
 	if (WindowFromWidget(widget)) {
 #if GTK_CHECK_VERSION(3,22,0)
 		// Appears unnecessary
 #elif GTK_CHECK_VERSION(3,0,0)
-		gdk_window_set_background_pattern(WindowFromWidget(widget), NULL);
+		gdk_window_set_background_pattern(WindowFromWidget(widget), nullptr);
 #else
-		gdk_window_set_back_pixmap(WindowFromWidget(widget), NULL, FALSE);
+		gdk_window_set_back_pixmap(WindowFromWidget(widget), nullptr, FALSE);
 #endif
 	}
 }
@@ -2463,12 +2508,12 @@ void ScintillaGTK::Dispose(GObject *object) {
 
 		if (PWidget(sciThis->scrollbarv)) {
 			gtk_widget_unparent(PWidget(sciThis->scrollbarv));
-			sciThis->scrollbarv = NULL;
+			sciThis->scrollbarv = nullptr;
 		}
 
 		if (PWidget(sciThis->scrollbarh)) {
 			gtk_widget_unparent(PWidget(sciThis->scrollbarh));
-			sciThis->scrollbarh = NULL;
+			sciThis->scrollbarh = nullptr;
 		}
 
 		scintilla_class_parent_class->dispose(object);
@@ -2489,7 +2534,7 @@ void ScintillaGTK::Destroy(GObject *object) {
 		sciThis->Finalise();
 
 		delete sciThis;
-		scio->pscin = 0;
+		scio->pscin = nullptr;
 		scintilla_class_parent_class->finalize(object);
 	} catch (...) {
 		// Its dead so nowhere to save the status
@@ -2505,7 +2550,7 @@ gboolean ScintillaGTK::DrawTextThis(cairo_t *cr) {
 
 		rcPaint = GetClientRectangle();
 
-		PLATFORM_ASSERT(rgnUpdate == NULL);
+		PLATFORM_ASSERT(rgnUpdate == nullptr);
 		rgnUpdate = cairo_copy_clip_rectangle_list(cr);
 		if (rgnUpdate && rgnUpdate->status != CAIRO_STATUS_SUCCESS) {
 			// If not successful then ignore
@@ -2561,26 +2606,26 @@ gboolean ScintillaGTK::DrawThis(cairo_t *cr) {
 			gtk_style_context_add_class(styleContext, GTK_STYLE_CLASS_SCROLLBARS_JUNCTION);
 
 			gtk_render_background(styleContext, cr, rc.right, rc.bottom,
-					verticalScrollBarWidth, horizontalScrollBarHeight);
+					      verticalScrollBarWidth, horizontalScrollBarHeight);
 			gtk_render_frame(styleContext, cr, rc.right, rc.bottom,
-					verticalScrollBarWidth, horizontalScrollBarHeight);
+					 verticalScrollBarWidth, horizontalScrollBarHeight);
 
 			gtk_style_context_restore(styleContext);
 		}
 #endif
 
 		gtk_container_propagate_draw(
-		    GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarh), cr);
+			GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarh), cr);
 		gtk_container_propagate_draw(
-		    GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarv), cr);
+			GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarv), cr);
 // Starting from the following version, the expose event are not propagated
 // for double buffered non native windows, so we need to call it ourselves
 // or keep the default handler
 #if GTK_CHECK_VERSION(3,0,0)
 		// we want to forward on any >= 3.9.2 runtime
-		if (gtk_check_version(3,9,2) == NULL) {
+		if (gtk_check_version(3, 9, 2) == nullptr) {
 			gtk_container_propagate_draw(
-					GTK_CONTAINER(PWidget(wMain)), PWidget(wText), cr);
+				GTK_CONTAINER(PWidget(wMain)), PWidget(wText), cr);
 		}
 #endif
 	} catch (...) {
@@ -2600,14 +2645,15 @@ gboolean ScintillaGTK::ExposeTextThis(GtkWidget * /*widget*/, GdkEventExpose *os
 	try {
 		paintState = painting;
 
-		rcPaint.left = ose->area.x;
-		rcPaint.top = ose->area.y;
-		rcPaint.right = ose->area.x + ose->area.width;
-		rcPaint.bottom = ose->area.y + ose->area.height;
+		rcPaint = PRectangle::FromInts(
+				  ose->area.x,
+				  ose->area.y,
+				  ose->area.x + ose->area.width,
+				  ose->area.y + ose->area.height);
 
-		PLATFORM_ASSERT(rgnUpdate == NULL);
+		PLATFORM_ASSERT(rgnUpdate == nullptr);
 		rgnUpdate = gdk_region_copy(ose->region);
-		PRectangle rcClient = GetClientRectangle();
+		const PRectangle rcClient = GetClientRectangle();
 		paintingAllText = rcPaint.Contains(rcClient);
 		std::unique_ptr<Surface> surfaceWindow(Surface::Allocate(SC_TECHNOLOGY_DEFAULT));
 		cairo_t *cr = gdk_cairo_create(PWindow(wText));
@@ -2625,7 +2671,7 @@ gboolean ScintillaGTK::ExposeTextThis(GtkWidget * /*widget*/, GdkEventExpose *os
 		if (rgnUpdate) {
 			gdk_region_destroy(rgnUpdate);
 		}
-		rgnUpdate = 0;
+		rgnUpdate = nullptr;
 	} catch (...) {
 		errorStatus = SC_STATUS_FAILURE;
 	}
@@ -2651,9 +2697,9 @@ gboolean ScintillaGTK::Expose(GtkWidget *, GdkEventExpose *ose) {
 
 		// The text is painted in ExposeText
 		gtk_container_propagate_expose(
-		    GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarh), ose);
+			GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarh), ose);
 		gtk_container_propagate_expose(
-		    GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarv), ose);
+			GTK_CONTAINER(PWidget(wMain)), PWidget(scrollbarv), ose);
 
 	} catch (...) {
 		errorStatus = SC_STATUS_FAILURE;
@@ -2680,14 +2726,14 @@ void ScintillaGTK::ScrollHSignal(GtkAdjustment *adj, ScintillaGTK *sciThis) {
 }
 
 void ScintillaGTK::SelectionReceived(GtkWidget *widget,
-                                     GtkSelectionData *selection_data, guint) {
+				     GtkSelectionData *selection_data, guint) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	//Platform::DebugPrintf("Selection received\n");
 	sciThis->ReceivedSelection(selection_data);
 }
 
 void ScintillaGTK::SelectionGet(GtkWidget *widget,
-                                GtkSelectionData *selection_data, guint info, guint) {
+				GtkSelectionData *selection_data, guint info, guint) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	try {
 		//Platform::DebugPrintf("Selection get\n");
@@ -2713,13 +2759,13 @@ gint ScintillaGTK::SelectionClear(GtkWidget *widget, GdkEventSelection *selectio
 }
 
 gboolean ScintillaGTK::DragMotionThis(GdkDragContext *context,
-                                 gint x, gint y, guint dragtime) {
+				      gint x, gint y, guint dragtime) {
 	try {
-		Point npt(x, y);
+		const Point npt = Point::FromInts(x, y);
 		SetDragPosition(SPositionFromLocation(npt, false, false, UserVirtualSpace()));
 		GdkDragAction preferredAction = gdk_drag_context_get_suggested_action(context);
-		GdkDragAction actions = gdk_drag_context_get_actions(context);
-		SelectionPosition pos = SPositionFromLocation(npt);
+		const GdkDragAction actions = gdk_drag_context_get_actions(context);
+		const SelectionPosition pos = SPositionFromLocation(npt);
 		if ((inDragDrop == ddDragging) && (PositionInSelection(pos.Position()))) {
 			// Avoid dragging selection onto itself as that produces a move
 			// with no real effect but which creates undo actions.
@@ -2735,7 +2781,7 @@ gboolean ScintillaGTK::DragMotionThis(GdkDragContext *context,
 }
 
 gboolean ScintillaGTK::DragMotion(GtkWidget *widget, GdkDragContext *context,
-                                 gint x, gint y, guint dragtime) {
+				  gint x, gint y, guint dragtime) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	return sciThis->DragMotionThis(context, x, y, dragtime);
 }
@@ -2765,7 +2811,7 @@ void ScintillaGTK::DragEnd(GtkWidget *widget, GdkDragContext * /*context*/) {
 }
 
 gboolean ScintillaGTK::Drop(GtkWidget *widget, GdkDragContext * /*context*/,
-                            gint, gint, guint) {
+			    gint, gint, guint) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	try {
 		//Platform::DebugPrintf("Drop %x\n", sciThis);
@@ -2777,7 +2823,7 @@ gboolean ScintillaGTK::Drop(GtkWidget *widget, GdkDragContext * /*context*/,
 }
 
 void ScintillaGTK::DragDataReceived(GtkWidget *widget, GdkDragContext * /*context*/,
-                                    gint, gint, GtkSelectionData *selection_data, guint /*info*/, guint) {
+				    gint, gint, GtkSelectionData *selection_data, guint /*info*/, guint) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	try {
 		sciThis->ReceivedDrop(selection_data);
@@ -2788,14 +2834,14 @@ void ScintillaGTK::DragDataReceived(GtkWidget *widget, GdkDragContext * /*contex
 }
 
 void ScintillaGTK::DragDataGet(GtkWidget *widget, GdkDragContext *context,
-                               GtkSelectionData *selection_data, guint info, guint) {
+			       GtkSelectionData *selection_data, guint info, guint) {
 	ScintillaGTK *sciThis = FromWidget(widget);
 	try {
 		sciThis->dragWasDropped = true;
 		if (!sciThis->sel.Empty()) {
 			sciThis->GetSelection(selection_data, info, &sciThis->drag);
 		}
-		GdkDragAction action = gdk_drag_context_get_selected_action(context);
+		const GdkDragAction action = gdk_drag_context_get_selected_action(context);
 		if (action == GDK_ACTION_MOVE) {
 			for (size_t r=0; r<sciThis->sel.Count(); r++) {
 				if (sciThis->posDrop >= sciThis->sel.Range(r).Start()) {
@@ -2824,7 +2870,7 @@ gboolean ScintillaGTK::IdleCallback(gpointer pSci) {
 	ScintillaGTK *sciThis = static_cast<ScintillaGTK *>(pSci);
 	// Idler will be automatically stopped, if there is nothing
 	// to do while idle.
-	bool ret = sciThis->Idle();
+	const bool ret = sciThis->Idle();
 	if (ret == false) {
 		// FIXME: This will remove the idler from GTK, we don't want to
 		// remove it as it is removed automatically when this function
@@ -2850,13 +2896,13 @@ void ScintillaGTK::QueueIdleWork(WorkNeeded::workItems items, Sci::Position upTo
 	Editor::QueueIdleWork(items, upTo);
 	if (!styleIdleID) {
 		// Only allow one style needed to be queued
-		styleIdleID = gdk_threads_add_idle_full(G_PRIORITY_HIGH_IDLE, StyleIdle, this, NULL);
+		styleIdleID = gdk_threads_add_idle_full(G_PRIORITY_HIGH_IDLE, StyleIdle, this, nullptr);
 	}
 }
 
 void ScintillaGTK::SetDocPointer(Document *document) {
-	Document *oldDoc = 0;
-	ScintillaGTKAccessible *sciAccessible = 0;
+	Document *oldDoc = nullptr;
+	ScintillaGTKAccessible *sciAccessible = nullptr;
 	if (accessible) {
 		sciAccessible = ScintillaGTKAccessible::FromAccessible(accessible);
 		if (sciAccessible && pdoc) {
@@ -2877,7 +2923,7 @@ void ScintillaGTK::SetDocPointer(Document *document) {
 }
 
 void ScintillaGTK::PopUpCB(GtkMenuItem *menuItem, ScintillaGTK *sciThis) {
-	guint action = GPOINTER_TO_UINT(g_object_get_data(G_OBJECT(menuItem), "CmdNum"));
+	guint const action = GPOINTER_TO_UINT(g_object_get_data(G_OBJECT(menuItem), "CmdNum"));
 	if (action) {
 		sciThis->Command(action);
 	}
@@ -2889,9 +2935,7 @@ gboolean ScintillaGTK::PressCT(GtkWidget *widget, GdkEventButton *event, Scintil
 			return FALSE;
 		if (event->type != GDK_BUTTON_PRESS)
 			return FALSE;
-		Point pt;
-		pt.x = int(event->x);
-		pt.y = int(event->y);
+		const Point pt = PointOfEvent(event);
 		sciThis->ct.MouseClick(pt);
 		sciThis->CallTipClick();
 	} catch (...) {
@@ -2935,16 +2979,16 @@ gboolean ScintillaGTK::ExposeCT(GtkWidget *widget, GdkEventExpose * /*ose*/, Cal
 
 #endif
 
-AtkObject* ScintillaGTK::GetAccessibleThis(GtkWidget *widget) {
+AtkObject *ScintillaGTK::GetAccessibleThis(GtkWidget *widget) {
 	return ScintillaGTKAccessible::WidgetGetAccessibleImpl(widget, &accessible, scintilla_class_parent_class);
 }
 
-AtkObject* ScintillaGTK::GetAccessible(GtkWidget *widget) {
+AtkObject *ScintillaGTK::GetAccessible(GtkWidget *widget) {
 	return FromWidget(widget)->GetAccessibleThis(widget);
 }
 
 sptr_t ScintillaGTK::DirectFunction(
-    sptr_t ptr, unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
+	sptr_t ptr, unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 	return reinterpret_cast<ScintillaGTK *>(ptr)->WndProc(iMessage, wParam, lParam);
 }
 
@@ -2976,19 +3020,19 @@ GType scintilla_get_type() {
 			scintilla_type = g_type_from_name("ScintillaObject");
 			if (!scintilla_type) {
 				static GTypeInfo scintilla_info = {
-					(guint16) sizeof (ScintillaObjectClass),
-					NULL, //(GBaseInitFunc)
-					NULL, //(GBaseFinalizeFunc)
+					(guint16) sizeof(ScintillaObjectClass),
+					nullptr, //(GBaseInitFunc)
+					nullptr, //(GBaseFinalizeFunc)
 					(GClassInitFunc) scintilla_class_init,
-					NULL, //(GClassFinalizeFunc)
-					NULL, //gconstpointer data
-					(guint16) sizeof (ScintillaObject),
+					nullptr, //(GClassFinalizeFunc)
+					nullptr, //gconstpointer data
+					(guint16) sizeof(ScintillaObject),
 					0, //n_preallocs
 					(GInstanceInitFunc) scintilla_init,
-					NULL //(GTypeValueTable*)
+					nullptr //(GTypeValueTable*)
 				};
 				scintilla_type = g_type_register_static(
-				            GTK_TYPE_CONTAINER, "ScintillaObject", &scintilla_info, (GTypeFlags) 0);
+							 GTK_TYPE_CONTAINER, "ScintillaObject", &scintilla_info, (GTypeFlags) 0);
 			}
 		}
 
@@ -3002,12 +3046,11 @@ GType scintilla_object_get_type() {
 	return scintilla_get_type();
 }
 
-void ScintillaGTK::ClassInit(OBJECT_CLASS* object_class, GtkWidgetClass *widget_class, GtkContainerClass *container_class) {
+void ScintillaGTK::ClassInit(OBJECT_CLASS *object_class, GtkWidgetClass *widget_class, GtkContainerClass *container_class) {
 	Platform_Initialise();
 #ifdef SCI_LEXER
 	Scintilla_LinkLexers();
 #endif
-	atomClipboard = gdk_atom_intern("CLIPBOARD", FALSE);
 	atomUTF8 = gdk_atom_intern("UTF8_STRING", FALSE);
 	atomString = GDK_SELECTION_TYPE_STRING;
 	atomUriList = gdk_atom_intern("text/uri-list", FALSE);
@@ -3062,35 +3105,35 @@ void ScintillaGTK::ClassInit(OBJECT_CLASS* object_class, GtkWidgetClass *widget_
 
 static void scintilla_class_init(ScintillaClass *klass) {
 	try {
-		OBJECT_CLASS *object_class = (OBJECT_CLASS*) klass;
-		GtkWidgetClass *widget_class = (GtkWidgetClass*) klass;
-		GtkContainerClass *container_class = (GtkContainerClass*) klass;
+		OBJECT_CLASS *object_class = (OBJECT_CLASS *) klass;
+		GtkWidgetClass *widget_class = (GtkWidgetClass *) klass;
+		GtkContainerClass *container_class = (GtkContainerClass *) klass;
 
-		GSignalFlags sigflags = GSignalFlags(G_SIGNAL_ACTION | G_SIGNAL_RUN_LAST);
+		const GSignalFlags sigflags = GSignalFlags(G_SIGNAL_ACTION | G_SIGNAL_RUN_LAST);
 		scintilla_signals[COMMAND_SIGNAL] = g_signal_new(
-		            "command",
-		            G_TYPE_FROM_CLASS(object_class),
-		            sigflags,
-		            G_STRUCT_OFFSET(ScintillaClass, command),
-		            NULL, //(GSignalAccumulator)
-		            NULL, //(gpointer)
-		            scintilla_marshal_VOID__INT_OBJECT,
-		            G_TYPE_NONE,
-		            2, G_TYPE_INT, GTK_TYPE_WIDGET);
+				"command",
+				G_TYPE_FROM_CLASS(object_class),
+				sigflags,
+				G_STRUCT_OFFSET(ScintillaClass, command),
+				nullptr, //(GSignalAccumulator)
+				nullptr, //(gpointer)
+				scintilla_marshal_VOID__INT_OBJECT,
+				G_TYPE_NONE,
+				2, G_TYPE_INT, GTK_TYPE_WIDGET);
 
 		scintilla_signals[NOTIFY_SIGNAL] = g_signal_new(
-		            SCINTILLA_NOTIFY,
-		            G_TYPE_FROM_CLASS(object_class),
-		            sigflags,
-		            G_STRUCT_OFFSET(ScintillaClass, notify),
-		            NULL, //(GSignalAccumulator)
-		            NULL, //(gpointer)
-		            scintilla_marshal_VOID__INT_BOXED,
-		            G_TYPE_NONE,
-		            2, G_TYPE_INT, SCINTILLA_TYPE_NOTIFICATION);
-
-		klass->command = NULL;
-		klass->notify = NULL;
+				SCINTILLA_NOTIFY,
+				G_TYPE_FROM_CLASS(object_class),
+				sigflags,
+				G_STRUCT_OFFSET(ScintillaClass, notify),
+				nullptr, //(GSignalAccumulator)
+				nullptr, //(gpointer)
+				scintilla_marshal_VOID__INT_BOXED,
+				G_TYPE_NONE,
+				2, G_TYPE_INT, SCINTILLA_TYPE_NOTIFICATION);
+
+		klass->command = nullptr;
+		klass->notify = nullptr;
 		scintilla_class_parent_class = G_OBJECT_CLASS(g_type_class_peek_parent(klass));
 		ScintillaGTK::ClassInit(object_class, widget_class, container_class);
 	} catch (...) {
@@ -3107,8 +3150,8 @@ static void scintilla_init(ScintillaObject *sci) {
 
 /* legacy name for scintilla_object_new */
 GEANY_API_SYMBOL
-GtkWidget* scintilla_new() {
-	GtkWidget *widget = GTK_WIDGET(g_object_new(scintilla_get_type(), NULL));
+GtkWidget *scintilla_new() {
+	GtkWidget *widget = GTK_WIDGET(g_object_new(scintilla_get_type(), nullptr));
 	gtk_widget_set_direction(widget, GTK_TEXT_DIR_LTR);
 
 	return widget;
@@ -3141,10 +3184,10 @@ GEANY_API_SYMBOL
 GType scnotification_get_type(void) {
 	static gsize type_id = 0;
 	if (g_once_init_enter(&type_id)) {
-		gsize id = (gsize) g_boxed_type_register_static(
-		                            g_intern_static_string("SCNotification"),
-		                            (GBoxedCopyFunc) copy_,
-		                            (GBoxedFreeFunc) free_);
+		const gsize id = (gsize) g_boxed_type_register_static(
+					 g_intern_static_string("SCNotification"),
+					 (GBoxedCopyFunc) copy_,
+					 (GBoxedFreeFunc) free_);
 		g_once_init_leave(&type_id, id);
 	}
 	return (GType) type_id;
diff --git a/scintilla/gtk/ScintillaGTK.h b/scintilla/gtk/ScintillaGTK.h
index 7cff34ff38..b878088244 100644
--- a/scintilla/gtk/ScintillaGTK.h
+++ b/scintilla/gtk/ScintillaGTK.h
@@ -36,7 +36,6 @@ class ScintillaGTK : public ScintillaBase {
 
 	GtkWidgetClass *parentClass;
 
-	static GdkAtom atomClipboard;
 	static GdkAtom atomUTF8;
 	static GdkAtom atomString;
 	static GdkAtom atomUriList;
@@ -80,7 +79,7 @@ class ScintillaGTK : public ScintillaBase {
 	ScintillaGTK &operator=(ScintillaGTK &&) = delete;
 	virtual ~ScintillaGTK();
 	static ScintillaGTK *FromWidget(GtkWidget *widget);
-	static void ClassInit(OBJECT_CLASS* object_class, GtkWidgetClass *widget_class, GtkContainerClass *container_class);
+	static void ClassInit(OBJECT_CLASS *object_class, GtkWidgetClass *widget_class, GtkContainerClass *container_class);
 private:
 	void Init();
 	void Finalise() override;
@@ -99,7 +98,7 @@ class ScintillaGTK : public ScintillaBase {
 		TickReason reason;
 		ScintillaGTK *scintilla;
 		guint timer;
-		TimeThunk() : reason(tickCaret), scintilla(NULL), timer(0) {}
+		TimeThunk() noexcept : reason(tickCaret), scintilla(nullptr), timer(0) {}
 	};
 	TimeThunk timers[tickDwell+1];
 	bool FineTickerRunning(TickReason reason) override;
@@ -127,18 +126,24 @@ class ScintillaGTK : public ScintillaBase {
 	int KeyDefault(int key, int modifiers) override;
 	void CopyToClipboard(const SelectionText &selectedText) override;
 	void Copy() override;
+	void RequestSelection(GdkAtom atomSelection);
 	void Paste() override;
 	void CreateCallTipWindow(PRectangle rc) override;
 	void AddToPopUp(const char *label, int cmd = 0, bool enabled = true) override;
 	bool OwnPrimarySelection();
 	void ClaimSelection() override;
 	void GetGtkSelectionText(GtkSelectionData *selectionData, SelectionText &selText);
+	void InsertSelection(GtkSelectionData *selectionData);
+public:	// Public for SelectionReceiver
+	GObject *MainObject() const noexcept;
+	void ReceivedClipboard(GtkSelectionData *selection_data) noexcept;
+private:
 	void ReceivedSelection(GtkSelectionData *selection_data);
 	void ReceivedDrop(GtkSelectionData *selection_data);
 	static void GetSelection(GtkSelectionData *selection_data, guint info, SelectionText *text);
 	void StoreOnClipboard(SelectionText *clipText);
-	static void ClipboardGetSelection(GtkClipboard* clip, GtkSelectionData *selection_data, guint info, void *data);
-	static void ClipboardClearSelection(GtkClipboard* clip, void *data);
+	static void ClipboardGetSelection(GtkClipboard *clip, GtkSelectionData *selection_data, guint info, void *data);
+	static void ClipboardClearSelection(GtkClipboard *clip, void *data);
 
 	void UnclaimSelection(GdkEventSelection *selection_event);
 	static void PrimarySelection(GtkWidget *widget, GtkSelectionData *selection_data, guint info, guint time_stamp, ScintillaGTK *sciThis);
@@ -195,8 +200,8 @@ class ScintillaGTK : public ScintillaBase {
 	gboolean ExposePreeditThis(GtkWidget *widget, GdkEventExpose *ose);
 	static gboolean ExposePreedit(GtkWidget *widget, GdkEventExpose *ose, ScintillaGTK *sciThis);
 #endif
-	AtkObject* GetAccessibleThis(GtkWidget *widget);
-	static AtkObject* GetAccessible(GtkWidget *widget);
+	AtkObject *GetAccessibleThis(GtkWidget *widget);
+	static AtkObject *GetAccessible(GtkWidget *widget);
 
 	bool KoreanIME();
 	void CommitThis(char *commitStr);
@@ -208,27 +213,27 @@ class ScintillaGTK : public ScintillaBase {
 	void DrawImeIndicator(int indicator, int len);
 	void SetCandidateWindowPos();
 
-	static void StyleSetText(GtkWidget *widget, GtkStyle *previous, void*);
-	static void RealizeText(GtkWidget *widget, void*);
+	static void StyleSetText(GtkWidget *widget, GtkStyle *previous, void *);
+	static void RealizeText(GtkWidget *widget, void *);
 	static void Dispose(GObject *object);
 	static void Destroy(GObject *object);
 	static void SelectionReceived(GtkWidget *widget, GtkSelectionData *selection_data,
-	                              guint time);
+				      guint time);
 	static void SelectionGet(GtkWidget *widget, GtkSelectionData *selection_data,
-	                         guint info, guint time);
+				 guint info, guint time);
 	static gint SelectionClear(GtkWidget *widget, GdkEventSelection *selection_event);
 	gboolean DragMotionThis(GdkDragContext *context, gint x, gint y, guint dragtime);
 	static gboolean DragMotion(GtkWidget *widget, GdkDragContext *context,
-	                           gint x, gint y, guint dragtime);
+				   gint x, gint y, guint dragtime);
 	static void DragLeave(GtkWidget *widget, GdkDragContext *context,
-	                      guint time);
+			      guint time);
 	static void DragEnd(GtkWidget *widget, GdkDragContext *context);
 	static gboolean Drop(GtkWidget *widget, GdkDragContext *context,
-	                     gint x, gint y, guint time);
+			     gint x, gint y, guint time);
 	static void DragDataReceived(GtkWidget *widget, GdkDragContext *context,
-	                             gint x, gint y, GtkSelectionData *selection_data, guint info, guint time);
+				     gint x, gint y, GtkSelectionData *selection_data, guint info, guint time);
 	static void DragDataGet(GtkWidget *widget, GdkDragContext *context,
-	                        GtkSelectionData *selection_data, guint info, guint time);
+				GtkSelectionData *selection_data, guint info, guint time);
 	static gboolean TimeOut(gpointer ptt);
 	static gboolean IdleCallback(gpointer pSci);
 	static gboolean StyleIdle(gpointer pSci);
@@ -245,7 +250,7 @@ class ScintillaGTK : public ScintillaBase {
 	static gboolean PressCT(GtkWidget *widget, GdkEventButton *event, ScintillaGTK *sciThis);
 
 	static sptr_t DirectFunction(sptr_t ptr,
-	                             unsigned int iMessage, uptr_t wParam, sptr_t lParam);
+				     unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 };
 
 // helper class to watch a GObject lifetime and get notified when it dies
@@ -256,16 +261,16 @@ class GObjectWatcher {
 		PLATFORM_ASSERT(obj == weakRef);
 
 		Destroyed();
-		weakRef = 0;
+		weakRef = nullptr;
 	}
 
 	static void WeakNotify(gpointer data, GObject *obj) {
-		static_cast<GObjectWatcher*>(data)->WeakNotifyThis(obj);
+		static_cast<GObjectWatcher *>(data)->WeakNotifyThis(obj);
 	}
 
 public:
 	GObjectWatcher(GObject *obj) :
-			weakRef(obj) {
+		weakRef(obj) {
 		g_object_weak_ref(weakRef, WeakNotify, this);
 	}
 
@@ -278,12 +283,12 @@ class GObjectWatcher {
 	virtual void Destroyed() {}
 
 	bool IsDestroyed() const {
-		return weakRef != 0;
+		return weakRef != nullptr;
 	}
 };
 
 std::string ConvertText(const char *s, size_t len, const char *charSetDest,
-                        const char *charSetSource, bool transliterations, bool silent=false);
+			const char *charSetSource, bool transliterations, bool silent=false);
 
 }
 
diff --git a/scintilla/gtk/ScintillaGTKAccessible.cxx b/scintilla/gtk/ScintillaGTKAccessible.cxx
index 40f5f19840..f9cedcb82f 100644
--- a/scintilla/gtk/ScintillaGTKAccessible.cxx
+++ b/scintilla/gtk/ScintillaGTKAccessible.cxx
@@ -77,7 +77,10 @@
 # include <gtk/gtk-a11y.h>
 #endif
 
-#if defined(__WIN32__) || defined(_MSC_VER)
+#if defined(_WIN32)
+// On Win32 use windows.h to access CLIPFORMAT
+#undef NOMINMAX
+#define NOMINMAX
 #include <windows.h>
 #endif
 
@@ -92,6 +95,7 @@
 #include "SciLexer.h"
 #endif
 #include "StringCopy.h"
+#include "CharacterCategory.h"
 #ifdef SCI_LEXER
 #include "LexerModule.h"
 #endif
@@ -147,7 +151,7 @@ ScintillaGTKAccessible *ScintillaGTKAccessible::FromAccessible(GtkAccessible *ac
 	// FIXME: do we need the check below?  GTK checks that in all methods, so maybe
 	GtkWidget *widget = gtk_accessible_get_widget(accessible);
 	if (! widget) {
-		return 0;
+		return nullptr;
 	}
 
 	return SCINTILLA_OBJECT_ACCESSIBLE_GET_PRIVATE(accessible)->pscin;
@@ -163,16 +167,16 @@ ScintillaGTKAccessible::ScintillaGTKAccessible(GtkAccessible *accessible_, GtkWi
 
 ScintillaGTKAccessible::~ScintillaGTKAccessible() {
 	if (gtk_accessible_get_widget(accessible)) {
-		g_signal_handlers_disconnect_matched(sci->sci, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, this);
+		g_signal_handlers_disconnect_matched(sci->sci, G_SIGNAL_MATCH_DATA, 0, 0, nullptr, nullptr, this);
 	}
 }
 
 gchar *ScintillaGTKAccessible::GetTextRangeUTF8(Sci::Position startByte, Sci::Position endByte) {
-	g_return_val_if_fail(startByte >= 0, NULL);
+	g_return_val_if_fail(startByte >= 0, nullptr);
 	// FIXME: should we swap start/end if necessary?
-	g_return_val_if_fail(endByte >= startByte, NULL);
+	g_return_val_if_fail(endByte >= startByte, nullptr);
 
-	gchar *utf8Text = NULL;
+	gchar *utf8Text = nullptr;
 	const char *charSetBuffer;
 
 	// like TargetAsUTF8, but avoids a double conversion
@@ -207,7 +211,7 @@ gchar *ScintillaGTKAccessible::GetText(int startChar, int endChar) {
 
 gchar *ScintillaGTKAccessible::GetTextAfterOffset(int charOffset,
 		AtkTextBoundary boundaryType, int *startChar, int *endChar) {
-	g_return_val_if_fail(charOffset >= 0, NULL);
+	g_return_val_if_fail(charOffset >= 0, nullptr);
 
 	Sci::Position startByte, endByte;
 	Sci::Position byteOffset = ByteOffsetFromCharacterOffset(charOffset);
@@ -249,7 +253,7 @@ gchar *ScintillaGTKAccessible::GetTextAfterOffset(int charOffset,
 
 		default:
 			*startChar = *endChar = -1;
-			return NULL;
+			return nullptr;
 	}
 
 	CharacterRangeFromByteRange(startByte, endByte, startChar, endChar);
@@ -258,7 +262,7 @@ gchar *ScintillaGTKAccessible::GetTextAfterOffset(int charOffset,
 
 gchar *ScintillaGTKAccessible::GetTextBeforeOffset(int charOffset,
 		AtkTextBoundary boundaryType, int *startChar, int *endChar) {
-	g_return_val_if_fail(charOffset >= 0, NULL);
+	g_return_val_if_fail(charOffset >= 0, nullptr);
 
 	Sci::Position startByte, endByte;
 	Sci::Position byteOffset = ByteOffsetFromCharacterOffset(charOffset);
@@ -311,7 +315,7 @@ gchar *ScintillaGTKAccessible::GetTextBeforeOffset(int charOffset,
 
 		default:
 			*startChar = *endChar = -1;
-			return NULL;
+			return nullptr;
 	}
 
 	CharacterRangeFromByteRange(startByte, endByte, startChar, endChar);
@@ -320,7 +324,7 @@ gchar *ScintillaGTKAccessible::GetTextBeforeOffset(int charOffset,
 
 gchar *ScintillaGTKAccessible::GetTextAtOffset(int charOffset,
 		AtkTextBoundary boundaryType, int *startChar, int *endChar) {
-	g_return_val_if_fail(charOffset >= 0, NULL);
+	g_return_val_if_fail(charOffset >= 0, nullptr);
 
 	Sci::Position startByte, endByte;
 	Sci::Position byteOffset = ByteOffsetFromCharacterOffset(charOffset);
@@ -373,7 +377,7 @@ gchar *ScintillaGTKAccessible::GetTextAtOffset(int charOffset,
 
 		default:
 			*startChar = *endChar = -1;
-			return NULL;
+			return nullptr;
 	}
 
 	CharacterRangeFromByteRange(startByte, endByte, startChar, endChar);
@@ -383,7 +387,7 @@ gchar *ScintillaGTKAccessible::GetTextAtOffset(int charOffset,
 #if ATK_CHECK_VERSION(2, 10, 0)
 gchar *ScintillaGTKAccessible::GetStringAtOffset(int charOffset,
 		AtkTextGranularity granularity, int *startChar, int *endChar) {
-	g_return_val_if_fail(charOffset >= 0, NULL);
+	g_return_val_if_fail(charOffset >= 0, nullptr);
 
 	Sci::Position startByte, endByte;
 	Sci::Position byteOffset = ByteOffsetFromCharacterOffset(charOffset);
@@ -405,7 +409,7 @@ gchar *ScintillaGTKAccessible::GetStringAtOffset(int charOffset,
 		}
 		default:
 			*startChar = *endChar = -1;
-			return NULL;
+			return nullptr;
 	}
 
 	CharacterRangeFromByteRange(startByte, endByte, startChar, endChar);
@@ -527,10 +531,10 @@ static AtkAttributeSet *AddTextColorAttribute(AtkAttributeSet *attributes, AtkTe
 }
 
 AtkAttributeSet *ScintillaGTKAccessible::GetAttributesForStyle(unsigned int styleNum) {
-	AtkAttributeSet *attr_set = NULL;
+	AtkAttributeSet *attr_set = nullptr;
 
 	if (styleNum >= sci->vs.styles.size())
-		return NULL;
+		return nullptr;
 	Style &style = sci->vs.styles[styleNum];
 
 	attr_set = AddTextAttribute(attr_set, ATK_TEXT_ATTR_FAMILY_NAME, g_strdup(style.fontName));
@@ -547,7 +551,7 @@ AtkAttributeSet *ScintillaGTKAccessible::GetAttributesForStyle(unsigned int styl
 }
 
 AtkAttributeSet *ScintillaGTKAccessible::GetRunAttributes(int charOffset, int *startChar, int *endChar) {
-	g_return_val_if_fail(charOffset >= -1, NULL);
+	g_return_val_if_fail(charOffset >= -1, nullptr);
 
 	Sci::Position byteOffset;
 	if (charOffset == -1) {
@@ -557,7 +561,7 @@ AtkAttributeSet *ScintillaGTKAccessible::GetRunAttributes(int charOffset, int *s
 	}
 	int length = sci->pdoc->Length();
 
-	g_return_val_if_fail(byteOffset <= length, NULL);
+	g_return_val_if_fail(byteOffset <= length, nullptr);
 
 	const char style = StyleAt(byteOffset, true);
 	// compute the range for this style
@@ -583,7 +587,7 @@ gint ScintillaGTKAccessible::GetNSelections() {
 
 gchar *ScintillaGTKAccessible::GetSelection(gint selection_num, int *startChar, int *endChar) {
 	if (selection_num < 0 || (unsigned int) selection_num >= sci->sel.Count())
-		return NULL;
+		return nullptr;
 
 	Sci::Position startByte = sci->sel.Range(selection_num).Start().Position();
 	Sci::Position endByte = sci->sel.Range(selection_num).End().Position();
@@ -737,7 +741,7 @@ void ScintillaGTKAccessible::PasteText(int charPosition) {
 		Sci::Position bytePosition;
 
 		void Destroyed() override {
-			scia = 0;
+			scia = nullptr;
 		}
 
 		Helper(ScintillaGTKAccessible *scia_, Sci::Position bytePos_) :
@@ -763,7 +767,7 @@ void ScintillaGTKAccessible::PasteText(int charPosition) {
 		static void TextReceivedCallback(GtkClipboard *clipboard, const gchar *text, gpointer data) {
 			Helper *helper = static_cast<Helper*>(data);
 			try {
-				if (helper->scia != 0) {
+				if (helper->scia != nullptr) {
 					helper->TextReceived(clipboard, text);
 				}
 			} catch (...) {}
@@ -917,20 +921,20 @@ void ScintillaGTKAccessible::Notify(GtkWidget *, gint, SCNotification *nt) {
 
 // AtkText
 gchar *ScintillaGTKAccessible::AtkTextIface::GetText(AtkText *text, int start_offset, int end_offset) {
-	WRAPPER_METHOD_BODY(text, GetText(start_offset, end_offset), NULL);
+	WRAPPER_METHOD_BODY(text, GetText(start_offset, end_offset), nullptr);
 }
 gchar *ScintillaGTKAccessible::AtkTextIface::GetTextAfterOffset(AtkText *text, int offset, AtkTextBoundary boundary_type, int *start_offset, int *end_offset) {
-	WRAPPER_METHOD_BODY(text, GetTextAfterOffset(offset, boundary_type, start_offset, end_offset), NULL)
+	WRAPPER_METHOD_BODY(text, GetTextAfterOffset(offset, boundary_type, start_offset, end_offset), nullptr)
 }
 gchar *ScintillaGTKAccessible::AtkTextIface::GetTextBeforeOffset(AtkText *text, int offset, AtkTextBoundary boundary_type, int *start_offset, int *end_offset) {
-	WRAPPER_METHOD_BODY(text, GetTextBeforeOffset(offset, boundary_type, start_offset, end_offset), NULL)
+	WRAPPER_METHOD_BODY(text, GetTextBeforeOffset(offset, boundary_type, start_offset, end_offset), nullptr)
 }
 gchar *ScintillaGTKAccessible::AtkTextIface::GetTextAtOffset(AtkText *text, gint offset, AtkTextBoundary boundary_type, gint *start_offset, gint *end_offset) {
-	WRAPPER_METHOD_BODY(text, GetTextAtOffset(offset, boundary_type, start_offset, end_offset), NULL)
+	WRAPPER_METHOD_BODY(text, GetTextAtOffset(offset, boundary_type, start_offset, end_offset), nullptr)
 }
 #if ATK_CHECK_VERSION(2, 10, 0)
 gchar *ScintillaGTKAccessible::AtkTextIface::GetStringAtOffset(AtkText *text, gint offset, AtkTextGranularity granularity, gint *start_offset, gint *end_offset) {
-	WRAPPER_METHOD_BODY(text, GetStringAtOffset(offset, granularity, start_offset, end_offset), NULL)
+	WRAPPER_METHOD_BODY(text, GetStringAtOffset(offset, granularity, start_offset, end_offset), nullptr)
 }
 #endif
 gunichar ScintillaGTKAccessible::AtkTextIface::GetCharacterAtOffset(AtkText *text, gint offset) {
@@ -952,16 +956,16 @@ void ScintillaGTKAccessible::AtkTextIface::GetCharacterExtents(AtkText *text, gi
 	WRAPPER_METHOD_BODY(text, GetCharacterExtents(offset, x, y, width, height, coords), )
 }
 AtkAttributeSet *ScintillaGTKAccessible::AtkTextIface::GetRunAttributes(AtkText *text, gint offset, gint *start_offset, gint *end_offset) {
-	WRAPPER_METHOD_BODY(text, GetRunAttributes(offset, start_offset, end_offset), NULL)
+	WRAPPER_METHOD_BODY(text, GetRunAttributes(offset, start_offset, end_offset), nullptr)
 }
 AtkAttributeSet *ScintillaGTKAccessible::AtkTextIface::GetDefaultAttributes(AtkText *text) {
-	WRAPPER_METHOD_BODY(text, GetDefaultAttributes(), NULL)
+	WRAPPER_METHOD_BODY(text, GetDefaultAttributes(), nullptr)
 }
 gint ScintillaGTKAccessible::AtkTextIface::GetNSelections(AtkText *text) {
 	WRAPPER_METHOD_BODY(text, GetNSelections(), 0)
 }
 gchar *ScintillaGTKAccessible::AtkTextIface::GetSelection(AtkText *text, gint selection_num, gint *start_pos, gint *end_pos) {
-	WRAPPER_METHOD_BODY(text, GetSelection(selection_num, start_pos, end_pos), NULL)
+	WRAPPER_METHOD_BODY(text, GetSelection(selection_num, start_pos, end_pos), nullptr)
 }
 gboolean ScintillaGTKAccessible::AtkTextIface::AddSelection(AtkText *text, gint start, gint end) {
 	WRAPPER_METHOD_BODY(text, AddSelection(start, end), FALSE)
@@ -1000,7 +1004,7 @@ static GType scintilla_object_accessible_factory_get_type(void);
 
 static void scintilla_object_accessible_init(ScintillaObjectAccessible *accessible);
 static void scintilla_object_accessible_class_init(ScintillaObjectAccessibleClass *klass);
-static gpointer scintilla_object_accessible_parent_class = NULL;
+static gpointer scintilla_object_accessible_parent_class = nullptr;
 
 
 // @p parent_type is only required on GTK 3.2 to 3.6, and only on the first call
@@ -1010,27 +1014,27 @@ static GType scintilla_object_accessible_get_type(GType parent_type G_GNUC_UNUSE
 	if (g_once_init_enter(&type_id_result)) {
 		GTypeInfo tinfo = {
 			0,															/* class size */
-			(GBaseInitFunc) NULL,										/* base init */
-			(GBaseFinalizeFunc) NULL,									/* base finalize */
+			(GBaseInitFunc) nullptr,										/* base init */
+			(GBaseFinalizeFunc) nullptr,									/* base finalize */
 			(GClassInitFunc) scintilla_object_accessible_class_init,	/* class init */
-			(GClassFinalizeFunc) NULL,									/* class finalize */
-			NULL,														/* class data */
+			(GClassFinalizeFunc) nullptr,									/* class finalize */
+			nullptr,														/* class data */
 			0,															/* instance size */
 			0,															/* nb preallocs */
 			(GInstanceInitFunc) scintilla_object_accessible_init,		/* instance init */
-			NULL														/* value table */
+			nullptr														/* value table */
 		};
 
 		const GInterfaceInfo atk_text_info = {
 			(GInterfaceInitFunc) ScintillaGTKAccessible::AtkTextIface::init,
-			(GInterfaceFinalizeFunc) NULL,
-			NULL
+			(GInterfaceFinalizeFunc) nullptr,
+			nullptr
 		};
 
 		const GInterfaceInfo atk_editable_text_info = {
 			(GInterfaceInitFunc) ScintillaGTKAccessible::AtkEditableTextIface::init,
-			(GInterfaceFinalizeFunc) NULL,
-			NULL
+			(GInterfaceFinalizeFunc) nullptr,
+			nullptr
 		};
 
 #if HAVE_GTK_A11Y_H
@@ -1071,13 +1075,13 @@ static GType scintilla_object_accessible_get_type(GType parent_type G_GNUC_UNUSE
 }
 
 static AtkObject *scintilla_object_accessible_new(GType parent_type, GObject *obj) {
-	g_return_val_if_fail(SCINTILLA_IS_OBJECT(obj), NULL);
+	g_return_val_if_fail(SCINTILLA_IS_OBJECT(obj), nullptr);
 
 	AtkObject *accessible = (AtkObject *) g_object_new(scintilla_object_accessible_get_type(parent_type),
 #if HAVE_WIDGET_SET_UNSET
 		"widget", obj,
 #endif
-		NULL);
+		nullptr);
 	atk_object_initialize(accessible, obj);
 
 	return accessible;
@@ -1089,7 +1093,7 @@ static AtkObject *scintilla_object_accessible_new(GType parent_type, GObject *ob
 // @p cache pointer to store the AtkObject between repeated calls.  Might or might not be filled.
 // @p widget_parent_class pointer to the widget's parent class (to chain up method calls).
 AtkObject *ScintillaGTKAccessible::WidgetGetAccessibleImpl(GtkWidget *widget, AtkObject **cache, gpointer widget_parent_class G_GNUC_UNUSED) {
-	if (*cache != NULL) {
+	if (*cache != nullptr) {
 		return *cache;
 	}
 
@@ -1139,7 +1143,7 @@ static AtkStateSet *scintilla_object_accessible_ref_state_set(AtkObject *accessi
 	AtkStateSet *state_set = ATK_OBJECT_CLASS(scintilla_object_accessible_parent_class)->ref_state_set(accessible);
 
 	GtkWidget *widget = gtk_accessible_get_widget(GTK_ACCESSIBLE(accessible));
-	if (widget == NULL) {
+	if (widget == nullptr) {
 		atk_state_set_add_state(state_set, ATK_STATE_DEFUNCT);
 	} else {
 		if (! scintilla_send_message(SCINTILLA_OBJECT(widget), SCI_GETREADONLY, 0, 0))
@@ -1159,11 +1163,11 @@ static AtkStateSet *scintilla_object_accessible_ref_state_set(AtkObject *accessi
 
 static void scintilla_object_accessible_widget_set(GtkAccessible *accessible) {
 	GtkWidget *widget = gtk_accessible_get_widget(accessible);
-	if (widget == NULL)
+	if (widget == nullptr)
 		return;
 
 	ScintillaObjectAccessiblePrivate *priv = SCINTILLA_OBJECT_ACCESSIBLE_GET_PRIVATE(accessible);
-	if (priv->pscin != 0)
+	if (priv->pscin)
 		delete priv->pscin;
 	priv->pscin = new ScintillaGTKAccessible(accessible, widget);
 }
@@ -1171,7 +1175,7 @@ static void scintilla_object_accessible_widget_set(GtkAccessible *accessible) {
 #if HAVE_WIDGET_SET_UNSET
 static void scintilla_object_accessible_widget_unset(GtkAccessible *accessible) {
 	GtkWidget *widget = gtk_accessible_get_widget(accessible);
-	if (widget == NULL)
+	if (widget == nullptr)
 		return;
 
 	ScintillaObjectAccessiblePrivate *priv = SCINTILLA_OBJECT_ACCESSIBLE_GET_PRIVATE(accessible);
@@ -1195,7 +1199,7 @@ static void scintilla_object_accessible_finalize(GObject *object) {
 
 	if (priv->pscin) {
 		delete priv->pscin;
-		priv->pscin = 0;
+		priv->pscin = nullptr;
 	}
 
 	G_OBJECT_CLASS(scintilla_object_accessible_parent_class)->finalize(object);
@@ -1224,7 +1228,7 @@ static void scintilla_object_accessible_class_init(ScintillaObjectAccessibleClas
 static void scintilla_object_accessible_init(ScintillaObjectAccessible *accessible) {
 	ScintillaObjectAccessiblePrivate *priv = SCINTILLA_OBJECT_ACCESSIBLE_GET_PRIVATE(accessible);
 
-	priv->pscin = 0;
+	priv->pscin = nullptr;
 }
 
 #if HAVE_GTK_FACTORY
diff --git a/scintilla/include/Platform.h b/scintilla/include/Platform.h
index 654460901a..8f5417fe09 100644
--- a/scintilla/include/Platform.h
+++ b/scintilla/include/Platform.h
@@ -108,6 +108,18 @@ class Point {
 		return Point(static_cast<XYPOSITION>(x_), static_cast<XYPOSITION>(y_));
 	}
 
+	bool operator!=(Point other) const noexcept {
+		return (x != other.x) || (y != other.y);
+	}
+
+	Point operator+(Point other) const noexcept {
+		return Point(x + other.x, y + other.y);
+	}
+
+	Point operator-(Point other) const noexcept {
+		return Point(x - other.x, y - other.y);
+	}
+
 	// Other automatically defined methods (assignment, copy constructor, destructor) are fine
 };
 
diff --git a/scintilla/include/SciLexer.h b/scintilla/include/SciLexer.h
index 4613e48de3..ae20985cea 100644
--- a/scintilla/include/SciLexer.h
+++ b/scintilla/include/SciLexer.h
@@ -139,6 +139,7 @@
 #define SCLEX_STATA 124
 #define SCLEX_SAS 125
 #define SCLEX_NIM 126
+#define SCLEX_CIL 127
 #define SCLEX_LPEG 999
 #define SCLEX_AUTOMATIC 1000
 #define SCE_P_DEFAULT 0
@@ -1874,6 +1875,17 @@
 #define SCE_NIM_NUMERROR 14
 #define SCE_NIM_OPERATOR 15
 #define SCE_NIM_IDENTIFIER 16
+#define SCE_CIL_DEFAULT 0
+#define SCE_CIL_COMMENT 1
+#define SCE_CIL_COMMENTLINE 2
+#define SCE_CIL_WORD 3
+#define SCE_CIL_WORD2 4
+#define SCE_CIL_WORD3 5
+#define SCE_CIL_STRING 6
+#define SCE_CIL_LABEL 7
+#define SCE_CIL_OPERATOR 8
+#define SCE_CIL_IDENTIFIER 9
+#define SCE_CIL_STRINGEOL 10
 /* --Autogenerated -- end of section automatically generated from Scintilla.iface */
 
 #endif
diff --git a/scintilla/include/Scintilla.h b/scintilla/include/Scintilla.h
index 298103cea2..b4b4f2e7ec 100644
--- a/scintilla/include/Scintilla.h
+++ b/scintilla/include/Scintilla.h
@@ -135,6 +135,7 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SC_MARK_UNDERLINE 29
 #define SC_MARK_RGBAIMAGE 30
 #define SC_MARK_BOOKMARK 31
+#define SC_MARK_VERTICALBOOKMARK 32
 #define SC_MARK_CHARACTER 10000
 #define SC_MARKNUM_FOLDEREND 25
 #define SC_MARKNUM_FOLDEROPENMID 26
@@ -266,6 +267,8 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SCI_SETCARETPERIOD 2076
 #define SCI_SETWORDCHARS 2077
 #define SCI_GETWORDCHARS 2646
+#define SCI_SETCHARACTERCATEGORYOPTIMIZATION 2720
+#define SCI_GETCHARACTERCATEGORYOPTIMIZATION 2721
 #define SCI_BEGINUNDOACTION 2078
 #define SCI_ENDUNDOACTION 2079
 #define INDIC_PLAIN 0
@@ -490,6 +493,9 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SC_FOLDDISPLAYTEXT_STANDARD 1
 #define SC_FOLDDISPLAYTEXT_BOXED 2
 #define SCI_FOLDDISPLAYTEXTSETSTYLE 2701
+#define SCI_FOLDDISPLAYTEXTGETSTYLE 2707
+#define SCI_SETDEFAULTFOLDDISPLAYTEXT 2722
+#define SCI_GETDEFAULTFOLDDISPLAYTEXT 2723
 #define SC_FOLDACTION_CONTRACT 0
 #define SC_FOLDACTION_EXPAND 1
 #define SC_FOLDACTION_TOGGLE 2
@@ -829,6 +835,9 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define CARETSTYLE_INVISIBLE 0
 #define CARETSTYLE_LINE 1
 #define CARETSTYLE_BLOCK 2
+#define CARETSTYLE_OVERSTRIKE_BAR 0
+#define CARETSTYLE_OVERSTRIKE_BLOCK 16
+#define CARETSTYLE_INS_MASK 0xF
 #define SCI_SETCARETSTYLE 2512
 #define SCI_GETCARETSTYLE 2513
 #define SCI_SETINDICATORCURRENT 2500
diff --git a/scintilla/include/Scintilla.iface b/scintilla/include/Scintilla.iface
index 7cbb200203..c009371c10 100644
--- a/scintilla/include/Scintilla.iface
+++ b/scintilla/include/Scintilla.iface
@@ -304,6 +304,7 @@ val SC_MARK_AVAILABLE=28
 val SC_MARK_UNDERLINE=29
 val SC_MARK_RGBAIMAGE=30
 val SC_MARK_BOOKMARK=31
+val SC_MARK_VERTICALBOOKMARK=32
 
 val SC_MARK_CHARACTER=10000
 
@@ -610,6 +611,12 @@ set void SetWordChars=2077(, string characters)
 # Returns the number of characters
 get int GetWordChars=2646(, stringresult characters)
 
+# Set the number of characters to have directly indexed categories
+set void SetCharacterCategoryOptimization=2720(int countCharacters,)
+
+# Get the number of characters to have directly indexed categories
+get int GetCharacterCategoryOptimization=2721(,)
+
 # Start a sequence of actions that is undone and redone as a unit.
 # May be nested.
 fun void BeginUndoAction=2078(,)
@@ -1227,9 +1234,18 @@ val SC_FOLDDISPLAYTEXT_HIDDEN=0
 val SC_FOLDDISPLAYTEXT_STANDARD=1
 val SC_FOLDDISPLAYTEXT_BOXED=2
 
-# Set the style of fold display text
+# Set the style of fold display text.
 set void FoldDisplayTextSetStyle=2701(int style,)
 
+# Get the style of fold display text.
+get int FoldDisplayTextGetStyle=2707(,)
+
+# Set the default fold display text.
+fun void SetDefaultFoldDisplayText=2722(, string text)
+
+# Get the default fold display text.
+fun int GetDefaultFoldDisplayText=2723(, stringresult text)
+
 enu FoldAction=SC_FOLDACTION_
 val SC_FOLDACTION_CONTRACT=0
 val SC_FOLDACTION_EXPAND=1
@@ -2178,6 +2194,9 @@ enu CaretStyle=CARETSTYLE_
 val CARETSTYLE_INVISIBLE=0
 val CARETSTYLE_LINE=1
 val CARETSTYLE_BLOCK=2
+val CARETSTYLE_OVERSTRIKE_BAR=0
+val CARETSTYLE_OVERSTRIKE_BLOCK=16
+val CARETSTYLE_INS_MASK=0xF
 
 # Set the style of the caret to be drawn.
 set void SetCaretStyle=2512(int caretStyle,)
@@ -2956,6 +2975,7 @@ val SCLEX_MAXIMA=123
 val SCLEX_STATA=124
 val SCLEX_SAS=125
 val SCLEX_NIM=126
+val SCLEX_CIL=127
 val SCLEX_LPEG=999
 
 # When a lexer specifies its language as SCLEX_AUTOMATIC it receives a
@@ -4929,6 +4949,19 @@ val SCE_NIM_STRINGEOL=13
 val SCE_NIM_NUMERROR=14
 val SCE_NIM_OPERATOR=15
 val SCE_NIM_IDENTIFIER=16
+# Lexical states for SCLEX_CIL
+lex CIL=SCLEX_CIL SCE_CIL_
+val SCE_CIL_DEFAULT=0
+val SCE_CIL_COMMENT=1
+val SCE_CIL_COMMENTLINE=2
+val SCE_CIL_WORD=3
+val SCE_CIL_WORD2=4
+val SCE_CIL_WORD3=5
+val SCE_CIL_STRING=6
+val SCE_CIL_LABEL=7
+val SCE_CIL_OPERATOR=8
+val SCE_CIL_IDENTIFIER=9
+val SCE_CIL_STRINGEOL=10
 
 # Events
 
diff --git a/scintilla/lexers/LexCPP.cxx b/scintilla/lexers/LexCPP.cxx
index d6637784ad..06d4c0265a 100644
--- a/scintilla/lexers/LexCPP.cxx
+++ b/scintilla/lexers/LexCPP.cxx
@@ -18,6 +18,7 @@
 #include <vector>
 #include <map>
 #include <algorithm>
+#include <iterator>
 
 #include "ILexer.h"
 #include "Scintilla.h"
@@ -39,7 +40,7 @@ using namespace Scintilla;
 namespace {
 	// Use an unnamed namespace to protect the functions and classes from name conflicts
 
-bool IsSpaceEquiv(int state) noexcept {
+constexpr bool IsSpaceEquiv(int state) noexcept {
 	return (state <= SCE_C_COMMENTDOC) ||
 		// including SCE_C_DEFAULT, SCE_C_COMMENT, SCE_C_COMMENTLINE
 		(state == SCE_C_COMMENTLINEDOC) || (state == SCE_C_COMMENTDOCKEYWORD) ||
@@ -86,7 +87,7 @@ bool followsReturnKeyword(const StyleContext &sc, LexAccessor &styler) {
 	return !*s;
 }
 
-bool IsSpaceOrTab(int ch) noexcept {
+constexpr bool IsSpaceOrTab(int ch) noexcept {
 	return ch == ' ' || ch == '\t';
 }
 
@@ -145,7 +146,7 @@ void highlightTaskMarker(StyleContext &sc, LexAccessor &styler,
 	if ((isoperator(sc.chPrev) || IsASpace(sc.chPrev)) && markerList.Length()) {
 		const int lengthMarker = 50;
 		char marker[lengthMarker+1] = "";
-		const Sci_Position currPos = static_cast<Sci_Position>(sc.currentPos);
+		const Sci_Position currPos = sc.currentPos;
 		int i = 0;
 		while (i < lengthMarker) {
 			const char ch = styler.SafeGetCharAt(currPos + i);
@@ -173,7 +174,7 @@ struct EscapeSequence {
 	CharacterSet *escapeSetValid;
 	EscapeSequence() {
 		digitsLeft = 0;
-		escapeSetValid = 0;
+		escapeSetValid = nullptr;
 		setHexDigits = CharacterSet(CharacterSet::setDigits, "ABCDEFabcdef");
 		setOctDigits = CharacterSet(CharacterSet::setNone, "01234567");
 	}
@@ -226,7 +227,7 @@ std::string GetRestOfLine(LexAccessor &styler, Sci_Position start, bool allowSpa
 	return restOfLine;
 }
 
-bool IsStreamCommentStyle(int style) noexcept {
+constexpr bool IsStreamCommentStyle(int style) noexcept {
 	return style == SCE_C_COMMENT ||
 		style == SCE_C_COMMENTDOC ||
 		style == SCE_C_COMMENTDOCKEYWORD ||
@@ -244,12 +245,24 @@ struct PPDefinition {
 	}
 };
 
+const int inactiveFlag = 0x40;
+
 class LinePPState {
-	int state;
-	int ifTaken;
-	int level;
+	// Track the state of preprocessor conditionals to allow showing active and inactive
+	// code in different styles.
+	// Only works up to 31 levels of conditional nesting.
+
+	// state is a bit mask with 1 bit per level
+	// bit is 1 for level if section inactive, so any bits set = inactive style
+	int state = 0;
+	// ifTaken is a bit mask with 1 bit per level
+	// bit is 1 for level if some branch at this level has been taken
+	int ifTaken = 0;
+	// level is the nesting level of #if constructs
+	int level = -1;
+	static const int maximumNestingLevel = 31;
 	bool ValidLevel() const noexcept {
-		return level >= 0 && level < 32;
+		return level >= 0 && level < maximumNestingLevel;
 	}
 	int maskLevel() const noexcept {
 		if (level >= 0) {
@@ -259,11 +272,17 @@ class LinePPState {
 		}
 	}
 public:
-	LinePPState() : state(0), ifTaken(0), level(-1) {
+	LinePPState() noexcept {
+	}
+	bool IsActive() const noexcept {
+		return state == 0;
 	}
 	bool IsInactive() const noexcept {
 		return state != 0;
 	}
+	int ActiveState() const noexcept {
+		return state ? inactiveFlag : 0;
+	}
 	bool CurrentIfTaken() const noexcept {
 		return (ifTaken & maskLevel()) != 0;
 	}
@@ -369,7 +388,7 @@ const char *const cppWordLists[] = {
             "Global classes and typedefs",
             "Preprocessor definitions",
             "Task marker and error marker keywords",
-            0,
+            nullptr,
 };
 
 struct OptionSetCPP : public OptionSet<OptionsCPP> {
@@ -500,7 +519,8 @@ class LexerCPP : public ILexerWithMetaData {
 	struct SymbolValue {
 		std::string value;
 		std::string arguments;
-		SymbolValue(const std::string &value_="", const std::string &arguments_="") : value(value_), arguments(arguments_) {
+		SymbolValue() = default;
+		SymbolValue(const std::string &value_, const std::string &arguments_) : value(value_), arguments(arguments_) {
 		}
 		SymbolValue &operator = (const std::string &value_) {
 			value = value_;
@@ -517,7 +537,6 @@ class LexerCPP : public ILexerWithMetaData {
 	OptionSetCPP osCPP;
 	EscapeSequence escapeSeq;
 	SparseState<std::string> rawStringTerminators;
-	enum { activeFlag = 0x40 };
 	enum { ssIdentifier, ssDocKeyword };
 	SubStyles subStyles;
 	std::string returnBuffer;
@@ -530,14 +549,19 @@ class LexerCPP : public ILexerWithMetaData {
 		setMultOp(CharacterSet::setNone, "*/%"),
 		setRelOp(CharacterSet::setNone, "=!<>"),
 		setLogicalOp(CharacterSet::setNone, "|&"),
-		subStyles(styleSubable, 0x80, 0x40, activeFlag) {
+		subStyles(styleSubable, 0x80, 0x40, inactiveFlag) {
 	}
+	// Deleted so LexerCPP objects can not be copied.
+	LexerCPP(const LexerCPP &) = delete;
+	LexerCPP(LexerCPP &&) = delete;
+	void operator=(const LexerCPP &) = delete;
+	void operator=(LexerCPP &&) = delete;
 	virtual ~LexerCPP() {
 	}
-	void SCI_METHOD Release() override {
+	void SCI_METHOD Release() noexcept override {
 		delete this;
 	}
-	int SCI_METHOD Version() const override {
+	int SCI_METHOD Version() const noexcept override {
 		return lvMetaData;
 	}
 	const char * SCI_METHOD PropertyNames() override {
@@ -557,11 +581,11 @@ class LexerCPP : public ILexerWithMetaData {
 	void SCI_METHOD Lex(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess) override;
 	void SCI_METHOD Fold(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess) override;
 
-	void * SCI_METHOD PrivateCall(int, void *) override {
-		return 0;
+	void * SCI_METHOD PrivateCall(int, void *) noexcept override {
+		return nullptr;
 	}
 
-	int SCI_METHOD LineEndTypesSupported() override {
+	int SCI_METHOD LineEndTypesSupported() noexcept override {
 		return SC_LINE_END_TYPE_UNICODE;
 	}
 
@@ -576,10 +600,10 @@ class LexerCPP : public ILexerWithMetaData {
 	}
 	int SCI_METHOD StyleFromSubStyle(int subStyle) override {
 		const int styleBase = subStyles.BaseStyle(MaskActive(subStyle));
-		const int active = subStyle & activeFlag;
-		return styleBase | active;
+		const int inactive = subStyle & inactiveFlag;
+		return styleBase | inactive;
 	}
-	int SCI_METHOD PrimaryStyleFromStyle(int style) override {
+	int SCI_METHOD PrimaryStyleFromStyle(int style) noexcept override {
 		return MaskActive(style);
 	}
 	void SCI_METHOD FreeSubStyles() override {
@@ -588,16 +612,16 @@ class LexerCPP : public ILexerWithMetaData {
 	void SCI_METHOD SetIdentifiers(int style, const char *identifiers) override {
 		subStyles.SetIdentifiers(style, identifiers);
 	}
-	int SCI_METHOD DistanceToSecondaryStyles() override {
-		return activeFlag;
+	int SCI_METHOD DistanceToSecondaryStyles() noexcept override {
+		return inactiveFlag;
 	}
-	const char * SCI_METHOD GetSubStyleBases() override {
+	const char * SCI_METHOD GetSubStyleBases() noexcept override {
 		return styleSubable;
 	}
 	int SCI_METHOD NamedStyles() override {
 		return std::max(subStyles.LastAllocated() + 1,
 			static_cast<int>(ELEMENTS(lexicalClasses))) +
-			activeFlag;
+			inactiveFlag;
 	}
 	const char * SCI_METHOD NameOfStyle(int style) override {
 		if (style >= NamedStyles())
@@ -615,11 +639,11 @@ class LexerCPP : public ILexerWithMetaData {
 		if (firstSubStyle >= 0) {
 			const int lastSubStyle = subStyles.LastAllocated();
 			if (((style >= firstSubStyle) && (style <= (lastSubStyle))) ||
-				((style >= firstSubStyle + activeFlag) && (style <= (lastSubStyle + activeFlag)))) {
+				((style >= firstSubStyle + inactiveFlag) && (style <= (lastSubStyle + inactiveFlag)))) {
 				int styleActive = style;
 				if (style > lastSubStyle) {
 					returnBuffer = "inactive ";
-					styleActive -= activeFlag;
+					styleActive -= inactiveFlag;
 				}
 				const int styleMain = StyleFromSubStyle(styleActive);
 				returnBuffer += lexicalClasses[styleMain].tags;
@@ -628,9 +652,9 @@ class LexerCPP : public ILexerWithMetaData {
 		}
 		if (style < static_cast<int>(ELEMENTS(lexicalClasses)))
 			return lexicalClasses[style].tags;
-		if (style >= activeFlag) {
+		if (style >= inactiveFlag) {
 			returnBuffer = "inactive ";
-			const int styleActive = style - activeFlag;
+			const int styleActive = style - inactiveFlag;
 			if (styleActive < static_cast<int>(ELEMENTS(lexicalClasses)))
 				returnBuffer += lexicalClasses[styleActive].tags;
 			else
@@ -654,8 +678,8 @@ class LexerCPP : public ILexerWithMetaData {
 	static ILexer *LexerFactoryCPPInsensitive() {
 		return new LexerCPP(false);
 	}
-	static int MaskActive(int style) noexcept {
-		return style & ~activeFlag;
+	constexpr static int MaskActive(int style) noexcept {
+		return style & ~inactiveFlag;
 	}
 	void EvaluateTokens(std::vector<std::string> &tokens, const SymbolTable &preprocessorDefinitions);
 	std::vector<std::string> Tokenize(const std::string &expr) const;
@@ -676,7 +700,7 @@ Sci_Position SCI_METHOD LexerCPP::PropertySet(const char *key, const char *val)
 }
 
 Sci_Position SCI_METHOD LexerCPP::WordListSet(int n, const char *wl) {
-	WordList *wordListN = 0;
+	WordList *wordListN = nullptr;
 	switch (n) {
 	case 0:
 		wordListN = &keywords;
@@ -813,12 +837,12 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 	std::string rawStringTerminator = rawStringTerminators.ValueAt(lineCurrent-1);
 	SparseState<std::string> rawSTNew(lineCurrent);
 
-	int activitySet = preproc.IsInactive() ? activeFlag : 0;
+	int activitySet = preproc.ActiveState();
 
 	const WordClassifier &classifierIdentifiers = subStyles.Classifier(SCE_C_IDENTIFIER);
 	const WordClassifier &classifierDocKeyWords = subStyles.Classifier(SCE_C_COMMENTDOCKEYWORD);
 
-	Sci_Position lineEndNext = styler.LineEnd(lineCurrent);
+	Sci_PositionU lineEndNext = styler.LineEnd(lineCurrent);
 
 	for (; sc.More();) {
 
@@ -840,7 +864,7 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 			isIncludePreprocessor = false;
 			inRERange = false;
 			if (preproc.IsInactive()) {
-				activitySet = activeFlag;
+				activitySet = inactiveFlag;
 				sc.SetState(sc.state | activitySet);
 			}
 		}
@@ -856,7 +880,7 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 
 		// Handle line continuation generically.
 		if (sc.ch == '\\') {
-			if (static_cast<Sci_Position>((sc.currentPos+1)) >= lineEndNext) {
+			if ((sc.currentPos+1) >= lineEndNext) {
 				lineCurrent++;
 				lineEndNext = styler.LineEnd(lineCurrent);
 				vlls.Add(lineCurrent, preproc);
@@ -950,7 +974,7 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 				break;
 			case SCE_C_PREPROCESSOR:
 				if (options.stylingWithinPreprocessor) {
-					if (IsASpace(sc.ch)) {
+					if (IsASpace(sc.ch) || (sc.ch == '(')) {
 						sc.SetState(SCE_C_DEFAULT|activitySet);
 					}
 				} else if (isStringInPreprocessor && (sc.Match('>') || sc.Match('\"') || sc.atLineEnd)) {
@@ -1128,7 +1152,7 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 					while ((sc.ch < 0x80) && islower(sc.ch))
 						sc.Forward();    // gobble regex flags
 					sc.SetState(SCE_C_DEFAULT|activitySet);
-				} else if (sc.ch == '\\' && (static_cast<Sci_Position>(sc.currentPos+1) < lineEndNext)) {
+				} else if (sc.ch == '\\' && ((sc.currentPos+1) < lineEndNext)) {
 					// Gobble up the escaped character
 					sc.Forward();
 				} else if (sc.ch == '[') {
@@ -1265,6 +1289,8 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 					isIncludePreprocessor = true;
 				} else {
 					if (options.trackPreprocessor) {
+						// If #if is nested too deeply (>31 levels) the active/inactive appearance
+						// will stop reflecting the code.
 						if (sc.Match("ifdef") || sc.Match("ifndef")) {
 							const bool isIfDef = sc.Match("ifdef");
 							const int startRest = isIfDef ? 5 : 6;
@@ -1276,47 +1302,58 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 							const bool ifGood = EvaluateExpression(restOfLine, preprocessorDefinitions);
 							preproc.StartSection(ifGood);
 						} else if (sc.Match("else")) {
+							// #else is shown as active if either preceding or following section is active
+							// as that means that it contributed to the result.
 							if (!preproc.CurrentIfTaken()) {
+								// Inactive, may become active if parent scope active
+								assert(sc.state == (SCE_C_PREPROCESSOR|inactiveFlag));
 								preproc.InvertCurrentLevel();
-								activitySet = preproc.IsInactive() ? activeFlag : 0;
+								activitySet = preproc.ActiveState();
+								// If following is active then show "else" as active
 								if (!activitySet)
-									sc.ChangeState(SCE_C_PREPROCESSOR|activitySet);
-							} else if (!preproc.IsInactive()) {
+									sc.ChangeState(SCE_C_PREPROCESSOR);
+							} else if (preproc.IsActive()) {
+								// Active -> inactive
+								assert(sc.state == SCE_C_PREPROCESSOR);
 								preproc.InvertCurrentLevel();
-								activitySet = preproc.IsInactive() ? activeFlag : 0;
-								if (!activitySet)
-									sc.ChangeState(SCE_C_PREPROCESSOR|activitySet);
+								activitySet = preproc.ActiveState();
+								// Continue to show "else" as active as it ends active section.
 							}
 						} else if (sc.Match("elif")) {
 							// Ensure only one chosen out of #if .. #elif .. #elif .. #else .. #endif
+							// #elif is shown as active if either preceding or following section is active
+							// as that means that it contributed to the result.
 							if (!preproc.CurrentIfTaken()) {
+								// Inactive, if expression true then may become active if parent scope active
+								assert(sc.state == (SCE_C_PREPROCESSOR|inactiveFlag));
 								// Similar to #if
 								std::string restOfLine = GetRestOfLine(styler, sc.currentPos + 4, true);
 								const bool ifGood = EvaluateExpression(restOfLine, preprocessorDefinitions);
 								if (ifGood) {
 									preproc.InvertCurrentLevel();
-									activitySet = preproc.IsInactive() ? activeFlag : 0;
+									activitySet = preproc.ActiveState();
 									if (!activitySet)
-										sc.ChangeState(SCE_C_PREPROCESSOR|activitySet);
+										sc.ChangeState(SCE_C_PREPROCESSOR);
 								}
-							} else if (!preproc.IsInactive()) {
+							} else if (preproc.IsActive()) {
+								// Active -> inactive
+								assert(sc.state == SCE_C_PREPROCESSOR);
 								preproc.InvertCurrentLevel();
-								activitySet = preproc.IsInactive() ? activeFlag : 0;
-								if (!activitySet)
-									sc.ChangeState(SCE_C_PREPROCESSOR|activitySet);
+								activitySet = preproc.ActiveState();
+								// Continue to show "elif" as active as it ends active section.
 							}
 						} else if (sc.Match("endif")) {
 							preproc.EndSection();
-							activitySet = preproc.IsInactive() ? activeFlag : 0;
+							activitySet = preproc.ActiveState();
 							sc.ChangeState(SCE_C_PREPROCESSOR|activitySet);
 						} else if (sc.Match("define")) {
-							if (options.updatePreprocessor && !preproc.IsInactive()) {
+							if (options.updatePreprocessor && preproc.IsActive()) {
 								std::string restOfLine = GetRestOfLine(styler, sc.currentPos + 6, true);
 								size_t startName = 0;
 								while ((startName < restOfLine.length()) && IsSpaceOrTab(restOfLine[startName]))
 									startName++;
 								size_t endName = startName;
-								while ((endName < restOfLine.length()) && setWord.Contains(static_cast<unsigned char>(restOfLine[endName])))
+								while ((endName < restOfLine.length()) && setWord.Contains(restOfLine[endName]))
 									endName++;
 								std::string key = restOfLine.substr(startName, endName-startName);
 								if ((endName < restOfLine.length()) && (restOfLine.at(endName) == '(')) {
@@ -1348,7 +1385,7 @@ void SCI_METHOD LexerCPP::Lex(Sci_PositionU startPos, Sci_Position length, int i
 								}
 							}
 						} else if (sc.Match("undef")) {
-							if (options.updatePreprocessor && !preproc.IsInactive()) {
+							if (options.updatePreprocessor && preproc.IsActive()) {
 								const std::string restOfLine = GetRestOfLine(styler, sc.currentPos + 5, false);
 								std::vector<std::string> tokens = Tokenize(restOfLine);
 								if (tokens.size() >= 1) {
@@ -1542,7 +1579,7 @@ void LexerCPP::EvaluateTokens(std::vector<std::string> &tokens, const SymbolTabl
 	size_t iterations = 0;	// Limit number of iterations in case there is a recursive macro.
 	for (size_t i = 0; (i<tokens.size()) && (iterations < maxIterations);) {
 		iterations++;
-		if (setWordStart.Contains(static_cast<unsigned char>(tokens[i][0]))) {
+		if (setWordStart.Contains(tokens[i][0])) {
 			SymbolTable::const_iterator it = preprocessorDefinitions.find(tokens[i]);
 			if (it != preprocessorDefinitions.end()) {
 				// Tokenize value
@@ -1569,7 +1606,7 @@ void LexerCPP::EvaluateTokens(std::vector<std::string> &tokens, const SymbolTabl
 						macroTokens.erase(std::remove_if(macroTokens.begin(), macroTokens.end(), OnlySpaceOrTab), macroTokens.end());
 
 						for (size_t iMacro = 0; iMacro < macroTokens.size();) {
-							if (setWordStart.Contains(static_cast<unsigned char>(macroTokens[iMacro][0]))) {
+							if (setWordStart.Contains(macroTokens[iMacro][0])) {
 								std::map<std::string, std::string>::const_iterator itFind = arguments.find(macroTokens[iMacro]);
 								if (itFind != arguments.end()) {
 									// TODO: Possible that value will be expression so should insert tokenized form
@@ -1687,9 +1724,9 @@ std::vector<std::string> LexerCPP::Tokenize(const std::string &expr) const {
 	const char *cp = expr.c_str();
 	while (*cp) {
 		std::string word;
-		if (setWord.Contains(static_cast<unsigned char>(*cp))) {
+		if (setWord.Contains(*cp)) {
 			// Identifiers and numbers
-			while (setWord.Contains(static_cast<unsigned char>(*cp))) {
+			while (setWord.Contains(*cp)) {
 				word += *cp;
 				cp++;
 			}
@@ -1698,17 +1735,17 @@ std::vector<std::string> LexerCPP::Tokenize(const std::string &expr) const {
 				word += *cp;
 				cp++;
 			}
-		} else if (setRelOp.Contains(static_cast<unsigned char>(*cp))) {
+		} else if (setRelOp.Contains(*cp)) {
 			word += *cp;
 			cp++;
-			if (setRelOp.Contains(static_cast<unsigned char>(*cp))) {
+			if (setRelOp.Contains(*cp)) {
 				word += *cp;
 				cp++;
 			}
-		} else if (setLogicalOp.Contains(static_cast<unsigned char>(*cp))) {
+		} else if (setLogicalOp.Contains(*cp)) {
 			word += *cp;
 			cp++;
-			if (setLogicalOp.Contains(static_cast<unsigned char>(*cp))) {
+			if (setLogicalOp.Contains(*cp)) {
 				word += *cp;
 				cp++;
 			}
diff --git a/scintilla/lexers/LexHaskell.cxx b/scintilla/lexers/LexHaskell.cxx
index 680a0f2965..bf81995483 100644
--- a/scintilla/lexers/LexHaskell.cxx
+++ b/scintilla/lexers/LexHaskell.cxx
@@ -26,6 +26,7 @@
 #include <ctype.h>
 
 #include <string>
+#include <vector>
 #include <map>
 
 #include "ILexer.h"
diff --git a/scintilla/lexers/LexTCL.cxx b/scintilla/lexers/LexTCL.cxx
index 0948f4880b..1ea6ecf6e8 100644
--- a/scintilla/lexers/LexTCL.cxx
+++ b/scintilla/lexers/LexTCL.cxx
@@ -128,8 +128,10 @@ static void ColouriseTCLDoc(Sci_PositionU startPos, Sci_Position length, int , W
 				continue;
 			case ',':
 				sc.SetState(SCE_TCL_OPERATOR);
-				if (subParen)
+				if (subParen) {
 					sc.ForwardSetState(SCE_TCL_SUBSTITUTION);
+					goto next;	// Already forwarded so avoid loop's Forward()
+				}
 				continue;
 			default :
 				// maybe spaces should be allowed ???
diff --git a/scintilla/lexlib/CharacterCategory.cxx b/scintilla/lexlib/CharacterCategory.cxx
index bc2fa23360..19c44cabe2 100644
--- a/scintilla/lexlib/CharacterCategory.cxx
+++ b/scintilla/lexlib/CharacterCategory.cxx
@@ -7,10 +7,13 @@
 // Copyright 2013 by Neil Hodgson <neilh@scintilla.org>
 // The License.txt file describes the conditions under which this software may be distributed.
 
+#include <vector>
 #include <algorithm>
 #include <iterator>
 
+#include "Scintilla.h" // for ptrdiff_t in Position.h
 #include "CharacterCategory.h"
+#include "Position.h" // for Sci::clamp
 
 namespace Scintilla {
 
@@ -3790,6 +3793,7 @@ const int catRanges[] = {
 33554397,
 33554460,
 35651549,
+35651613,
 //--Autogenerated -- end of section automatically generated
 };
 
@@ -3963,4 +3967,33 @@ bool IsXidContinue(int character) {
 	}
 }
 
+CharacterCategoryMap::CharacterCategoryMap() noexcept {
+	Optimize(256);
+}
+
+int CharacterCategoryMap::Size() const noexcept {
+	return static_cast<int>(dense.size());
+}
+
+void CharacterCategoryMap::Optimize(int countCharacters) {
+	const int characters = Sci::clamp(countCharacters, 256, maxUnicode + 1);
+	dense.resize(characters);
+
+	int end = 0;
+	int index = 0;
+	int current = catRanges[index];
+	++index;
+	do {
+		const int next = catRanges[index];
+		const unsigned char category = current & maskCategory;
+		current >>= 5;
+		end = std::min(characters, next >> 5);
+		while (current < end) {
+			dense[current++] = category;
+		}
+		current = next;
+		++index;
+	} while (characters > end);
+}
+
 }
diff --git a/scintilla/lexlib/CharacterCategory.h b/scintilla/lexlib/CharacterCategory.h
index 767d796702..d1ac391526 100644
--- a/scintilla/lexlib/CharacterCategory.h
+++ b/scintilla/lexlib/CharacterCategory.h
@@ -28,6 +28,23 @@ bool IsIdContinue(int character);
 bool IsXidStart(int character);
 bool IsXidContinue(int character);
 
+class CharacterCategoryMap {
+private:
+	std::vector<unsigned char> dense;
+public:
+	CharacterCategoryMap() noexcept;
+	CharacterCategory CategoryFor(int character) const {
+		if (static_cast<size_t>(character) < dense.size()) {
+			return static_cast<CharacterCategory>(dense[character]);
+		} else {
+			// binary search through ranges
+			return CategoriseCharacter(character);
+		}
+	}
+	int Size() const noexcept;
+	void Optimize(int countCharacters);
+};
+
 }
 
 #endif
diff --git a/scintilla/lexlib/CharacterSet.h b/scintilla/lexlib/CharacterSet.h
index 7c2a1fe48d..358f6bed3f 100644
--- a/scintilla/lexlib/CharacterSet.h
+++ b/scintilla/lexlib/CharacterSet.h
@@ -82,10 +82,9 @@ class CharacterSet {
 	}
 	void AddString(const char *setToAdd) {
 		for (const char *cp=setToAdd; *cp; cp++) {
-			int val = static_cast<unsigned char>(*cp);
-			assert(val >= 0);
-			assert(val < size);
-			bset[val] = true;
+			const unsigned char uch = *cp;
+			assert(uch < size);
+			bset[uch] = true;
 		}
 	}
 	bool Contains(int val) const {
@@ -93,6 +92,11 @@ class CharacterSet {
 		if (val < 0) return false;
 		return (val < size) ? bset[val] : valueAfter;
 	}
+	bool Contains(char ch) const {
+		// Overload char as char may be signed
+		const unsigned char uch = ch;
+		return Contains(uch);
+	}
 };
 
 // Functions for classifying characters
diff --git a/scintilla/lexlib/StyleContext.cxx b/scintilla/lexlib/StyleContext.cxx
index 683e21453e..fe56e53d7b 100644
--- a/scintilla/lexlib/StyleContext.cxx
+++ b/scintilla/lexlib/StyleContext.cxx
@@ -7,7 +7,6 @@
 
 #include <cstdlib>
 #include <cassert>
-#include <cctype>
 
 #include "ILexer.h"
 
diff --git a/scintilla/scintilla_changes.patch b/scintilla/scintilla_changes.patch
index 249c7b0a7b..f28072ea4a 100644
--- a/scintilla/scintilla_changes.patch
+++ b/scintilla/scintilla_changes.patch
@@ -39,8 +39,8 @@ index 0871ca2..49dc278 100644
  
  /* legacy name for scintilla_object_new */
 +GEANY_API_SYMBOL
- GtkWidget* scintilla_new() {
- 	GtkWidget *widget = GTK_WIDGET(g_object_new(scintilla_get_type(), NULL));
+ GtkWidget *scintilla_new() {
+ 	GtkWidget *widget = GTK_WIDGET(g_object_new(scintilla_get_type(), nullptr));
  	gtk_widget_set_direction(widget, GTK_TEXT_DIR_LTR);
 @@ -3207,6 +3212,7 @@ GtkWidget* scintilla_new() {
  	return widget;
@@ -62,7 +62,7 @@ diff --git scintilla/src/Catalogue.cxx scintilla/src/Catalogue.cxx
 index ed47aa8..e58f1ab 100644
 --- scintilla/src/Catalogue.cxx
 +++ scintilla/src/Catalogue.cxx
-@@ -77,128 +77,50 @@ int Scintilla_LinkLexers() {
+@@ -77,129 +77,50 @@ int Scintilla_LinkLexers() {
  
  //++Autogenerated -- run scripts/LexGen.py to regenerate
  //**\(\tLINK_LEXER(\*);\n\)
@@ -84,6 +84,7 @@ index ed47aa8..e58f1ab 100644
 -	LINK_LEXER(lmBlitzBasic);
 -	LINK_LEXER(lmBullant);
  	LINK_LEXER(lmCaml);
+-	LINK_LEXER(lmCIL);
 -	LINK_LEXER(lmClw);
 -	LINK_LEXER(lmClwNoCase);
  	LINK_LEXER(lmCmake);
diff --git a/scintilla/src/CallTip.cxx b/scintilla/src/CallTip.cxx
index 2dcf91ea63..18c4549bba 100644
--- a/scintilla/src/CallTip.cxx
+++ b/scintilla/src/CallTip.cxx
@@ -176,7 +176,7 @@ int CallTip::PaintContents(Surface *surfaceWindow, bool draw) {
 	PRectangle rcClient(1.0f, 1.0f, rcClientSize.right - 1, rcClientSize.bottom - 1);
 
 	// To make a nice small call tip window, it is only sized to fit most normal characters without accents
-	const int ascent = static_cast<int>(lround(surfaceWindow->Ascent(font) - surfaceWindow->InternalLeading(font)));
+	const int ascent = static_cast<int>(round(surfaceWindow->Ascent(font) - surfaceWindow->InternalLeading(font)));
 
 	// For each line...
 	// Draw the definition in three parts: before highlight, highlighted, after highlight
diff --git a/scintilla/src/CaseConvert.cxx b/scintilla/src/CaseConvert.cxx
index d578759968..c1cfd38e28 100644
--- a/scintilla/src/CaseConvert.cxx
+++ b/scintilla/src/CaseConvert.cxx
@@ -569,7 +569,7 @@ class CaseConverter : public ICaseConverter {
 	enum { maxConversionLength=6 };
 	struct ConversionString {
 		char conversion[maxConversionLength+1];
-		ConversionString() : conversion{} {
+		ConversionString() noexcept : conversion{} {
 		}
 	};
 	// Conversions are initially store in a vector of structs but then decomposed into
@@ -591,10 +591,10 @@ class CaseConverter : public ICaseConverter {
 	std::vector<ConversionString> conversions;
 
 public:
-	CaseConverter() {
+	CaseConverter() noexcept {
 	}
 	virtual ~CaseConverter() = default;
-	bool Initialised() const {
+	bool Initialised() const noexcept {
 		return !characters.empty();
 	}
 	void Add(int character, const char *conversion) {
@@ -771,7 +771,7 @@ void SetupConversions(enum CaseConversion conversion) {
 	}
 }
 
-CaseConverter *ConverterForConversion(enum CaseConversion conversion) {
+CaseConverter *ConverterForConversion(enum CaseConversion conversion) noexcept {
 	switch (conversion) {
 	case CaseConversionFold:
 		return &caseConvFold;
diff --git a/scintilla/src/CaseFolder.cxx b/scintilla/src/CaseFolder.cxx
index 0fd29c7bb6..7db4bb6797 100644
--- a/scintilla/src/CaseFolder.cxx
+++ b/scintilla/src/CaseFolder.cxx
@@ -41,7 +41,7 @@ void CaseFolderTable::SetTranslation(char ch, char chTranslation) {
 	mapping[static_cast<unsigned char>(ch)] = chTranslation;
 }
 
-void CaseFolderTable::StandardASCII() {
+void CaseFolderTable::StandardASCII() noexcept {
 	for (size_t iChar=0; iChar<sizeof(mapping); iChar++) {
 		if (iChar >= 'A' && iChar <= 'Z') {
 			mapping[iChar] = static_cast<char>(iChar - 'A' + 'a');
diff --git a/scintilla/src/CaseFolder.h b/scintilla/src/CaseFolder.h
index 5fa65870e0..eb852a491b 100644
--- a/scintilla/src/CaseFolder.h
+++ b/scintilla/src/CaseFolder.h
@@ -24,7 +24,7 @@ class CaseFolderTable : public CaseFolder {
 	~CaseFolderTable() override;
 	size_t Fold(char *folded, size_t sizeFolded, const char *mixed, size_t lenMixed) override;
 	void SetTranslation(char ch, char chTranslation);
-	void StandardASCII();
+	void StandardASCII() noexcept;
 };
 
 class ICaseConverter;
diff --git a/scintilla/src/CharClassify.cxx b/scintilla/src/CharClassify.cxx
index ba8433e62b..5ae47a2ef7 100644
--- a/scintilla/src/CharClassify.cxx
+++ b/scintilla/src/CharClassify.cxx
@@ -6,10 +6,11 @@
 // The License.txt file describes the conditions under which this software may be distributed.
 
 #include <cstdlib>
-#include <cctype>
+#include <cassert>
 
 #include <stdexcept>
 
+#include "CharacterSet.h"
 #include "CharClassify.h"
 
 using namespace Scintilla;
@@ -25,7 +26,7 @@ void CharClassify::SetDefaultCharClasses(bool includeWordClass) {
 			charClass[ch] = ccNewLine;
 		else if (ch < 0x20 || ch == ' ')
 			charClass[ch] = ccSpace;
-		else if (includeWordClass && (ch >= 0x80 || isalnum(ch) || ch == '_'))
+		else if (includeWordClass && (ch >= 0x80 || IsAlphaNumeric(ch) || ch == '_'))
 			charClass[ch] = ccWord;
 		else
 			charClass[ch] = ccPunctuation;
diff --git a/scintilla/src/ContractionState.cxx b/scintilla/src/ContractionState.cxx
index c5e352180e..47f345ada8 100644
--- a/scintilla/src/ContractionState.cxx
+++ b/scintilla/src/ContractionState.cxx
@@ -74,7 +74,6 @@ class ContractionState final : public IContractionState {
 	bool HiddenLines() const override;
 
 	const char *GetFoldDisplayText(Sci::Line lineDoc) const override;
-	bool GetFoldDisplayTextShown(Sci::Line lineDoc) const override;
 	bool SetFoldDisplayText(Sci::Line lineDoc, const char *text) override;
 
 	bool GetExpanded(Sci::Line lineDoc) const override;
@@ -276,17 +275,12 @@ const char *ContractionState<LINE>::GetFoldDisplayText(Sci::Line lineDoc) const
 	return foldDisplayTexts->ValueAt(lineDoc).get();
 }
 
-template <typename LINE>
-bool ContractionState<LINE>::GetFoldDisplayTextShown(Sci::Line lineDoc) const {
-	return !GetExpanded(lineDoc) && GetFoldDisplayText(lineDoc);
-}
-
 template <typename LINE>
 bool ContractionState<LINE>::SetFoldDisplayText(Sci::Line lineDoc, const char *text) {
 	EnsureData();
 	const char *foldText = foldDisplayTexts->ValueAt(lineDoc).get();
 	if (!foldText || !text || 0 != strcmp(text, foldText)) {
-		UniqueString uns = UniqueStringCopy(text);
+		UniqueString uns = IsNullOrEmpty(text) ? UniqueString() : UniqueStringCopy(text);
 		foldDisplayTexts->SetValueAt(lineDoc, std::move(uns));
 		Check();
 		return true;
diff --git a/scintilla/src/ContractionState.h b/scintilla/src/ContractionState.h
index 90f5c07845..f9ec7b6454 100644
--- a/scintilla/src/ContractionState.h
+++ b/scintilla/src/ContractionState.h
@@ -32,7 +32,6 @@ class IContractionState {
 	virtual bool HiddenLines() const=0;
 
 	virtual const char *GetFoldDisplayText(Sci::Line lineDoc) const=0;
-	virtual bool GetFoldDisplayTextShown(Sci::Line lineDoc) const=0;
 	virtual bool SetFoldDisplayText(Sci::Line lineDoc, const char *text)=0;
 
 	virtual bool GetExpanded(Sci::Line lineDoc) const=0;
diff --git a/scintilla/src/DBCS.h b/scintilla/src/DBCS.h
index ff3f9f22f8..58659ee3ee 100644
--- a/scintilla/src/DBCS.h
+++ b/scintilla/src/DBCS.h
@@ -10,6 +10,14 @@
 
 namespace Scintilla {
 
+constexpr bool IsDBCSCodePage(int codePage) noexcept {
+	return codePage == 932
+	       || codePage == 936
+	       || codePage == 949
+	       || codePage == 950
+	       || codePage == 1361;
+}
+
 bool DBCSIsLeadByte(int codePage, char ch) noexcept;
 
 }
diff --git a/scintilla/src/Document.cxx b/scintilla/src/Document.cxx
index 53c5280db8..dd11ae42dc 100644
--- a/scintilla/src/Document.cxx
+++ b/scintilla/src/Document.cxx
@@ -476,7 +476,7 @@ void Document::ClearLevels() {
 	Levels()->ClearLevels();
 }
 
-static bool IsSubordinate(int levelStart, int levelTry) {
+static bool IsSubordinate(int levelStart, int levelTry) noexcept {
 	if (levelTry & SC_FOLDLEVELWHITEFLAG)
 		return true;
 	else
@@ -1092,7 +1092,7 @@ int Document::DBCSDrawBytes(const char *text, int len) const noexcept {
 	}
 }
 
-static inline bool IsSpaceOrTab(int ch) noexcept {
+static constexpr bool IsSpaceOrTab(int ch) noexcept {
 	return ch == ' ' || ch == '\t';
 }
 
@@ -1438,7 +1438,7 @@ void Document::DelCharBack(Sci::Position pos) {
 	}
 }
 
-static Sci::Position NextTab(Sci::Position pos, Sci::Position tabSize) noexcept {
+static constexpr Sci::Position NextTab(Sci::Position pos, Sci::Position tabSize) noexcept {
 	return ((pos / tabSize) + 1) * tabSize;
 }
 
@@ -1710,7 +1710,7 @@ CharClassify::cc Document::WordCharacterClass(unsigned int ch) const {
 	if (dbcsCodePage && (!UTF8IsAscii(ch))) {
 		if (SC_CP_UTF8 == dbcsCodePage) {
 			// Use hard coded Unicode class
-			const CharacterCategory cc = CategoriseCharacter(ch);
+			const CharacterCategory cc = charMap.CategoryFor(ch);
 			switch (cc) {
 
 				// Separator, Line/Paragraph
@@ -2169,6 +2169,14 @@ int Document::GetCharsOfClass(CharClassify::cc characterClass, unsigned char *bu
     return charClass.GetCharsOfClass(characterClass, buffer);
 }
 
+void Document::SetCharacterCategoryOptimization(int countCharacters) {
+	charMap.Optimize(countCharacters);
+}
+
+int Document::CharacterCategoryOptimization() const noexcept {
+	return charMap.Size();
+}
+
 void SCI_METHOD Document::StartStyling(Sci_Position position, char) {
 	endStyled = position;
 }
@@ -2554,7 +2562,7 @@ Sci::Position Document::WordPartRight(Sci::Position pos) const {
 	return pos;
 }
 
-static bool IsLineEndChar(char c) noexcept {
+static constexpr bool IsLineEndChar(char c) noexcept {
 	return (c == '\n' || c == '\r');
 }
 
@@ -3061,16 +3069,9 @@ Sci::Position Cxx11RegexFindText(const Document *doc, Sci::Position minPos, Sci:
 
 		bool matched = false;
 		if (SC_CP_UTF8 == doc->dbcsCodePage) {
-			const size_t lenS = strlen(s);
-			std::vector<wchar_t> ws(lenS + 1);
-#if WCHAR_T_IS_16
-			const size_t outLen = UTF16FromUTF8(s, lenS, &ws[0], lenS);
-#else
-			const size_t outLen = UTF32FromUTF8(s, lenS, reinterpret_cast<unsigned int *>(&ws[0]), lenS);
-#endif
-			ws[outLen] = 0;
+			const std::wstring ws = WStringFromUTF8(s, strlen(s));
 			std::wregex regexp;
-			regexp.assign(&ws[0], flagsRe);
+			regexp.assign(ws, flagsRe);
 			matched = MatchOnLines<UTF8Iterator>(doc, regexp, resr, search);
 
 		} else {
diff --git a/scintilla/src/Document.h b/scintilla/src/Document.h
index 927bbd77c6..adbdc34138 100644
--- a/scintilla/src/Document.h
+++ b/scintilla/src/Document.h
@@ -126,11 +126,11 @@ struct StyledText {
 
 class HighlightDelimiter {
 public:
-	HighlightDelimiter() : isEnabled(false) {
+	HighlightDelimiter() noexcept : isEnabled(false) {
 		Clear();
 	}
 
-	void Clear() {
+	void Clear() noexcept {
 		beginFoldBlock = -1;
 		endFoldBlock = -1;
 		firstChangeableLineBefore = -1;
@@ -164,7 +164,7 @@ class HighlightDelimiter {
 	bool isEnabled;
 };
 
-inline int LevelNumber(int level) noexcept {
+constexpr int LevelNumber(int level) noexcept {
 	return level & SC_FOLDLEVELNUMBERMASK;
 }
 
@@ -174,13 +174,13 @@ class LexInterface {
 	ILexer *instance;
 	bool performingStyle;	///< Prevent reentrance
 public:
-	explicit LexInterface(Document *pdoc_) : pdoc(pdoc_), instance(nullptr), performingStyle(false) {
+	explicit LexInterface(Document *pdoc_) noexcept : pdoc(pdoc_), instance(nullptr), performingStyle(false) {
 	}
 	virtual ~LexInterface() {
 	}
 	void Colourise(Sci::Position start, Sci::Position end);
 	virtual int LineEndTypesSupported();
-	bool UseContainerLexing() const {
+	bool UseContainerLexing() const noexcept {
 		return instance == nullptr;
 	}
 };
@@ -230,6 +230,7 @@ class Document : PerLine, public IDocumentWithLineEnd, public ILoader {
 	int refCount;
 	CellBuffer cb;
 	CharClassify charClass;
+	CharacterCategoryMap charMap;
 	std::unique_ptr<CaseFolder> pcf;
 	Sci::Position endStyled;
 	int styleClock;
@@ -444,6 +445,8 @@ class Document : PerLine, public IDocumentWithLineEnd, public ILoader {
 	void SetDefaultCharClasses(bool includeWordClass);
 	void SetCharClasses(const unsigned char *chars, CharClassify::cc newCharClass);
 	int GetCharsOfClass(CharClassify::cc characterClass, unsigned char *buffer) const;
+	void SetCharacterCategoryOptimization(int countCharacters);
+	int CharacterCategoryOptimization() const noexcept;
 	void SCI_METHOD StartStyling(Sci_Position position, char mask) override;
 	bool SCI_METHOD SetStyleFor(Sci_Position length, char style) override;
 	bool SCI_METHOD SetStyles(Sci_Position length, const char *styles) override;
@@ -507,6 +510,11 @@ class UndoGroup {
 			pdoc->BeginUndoAction();
 		}
 	}
+	// Deleted so UndoGroup objects can not be copied.
+	UndoGroup(const UndoGroup &) = delete;
+	UndoGroup(UndoGroup &&) = delete;
+	void operator=(const UndoGroup &) = delete;
+	UndoGroup &operator=(UndoGroup &&) = delete;
 	~UndoGroup() {
 		if (groupNeeded) {
 			pdoc->EndUndoAction();
@@ -573,7 +581,7 @@ class DocWatcher {
 	virtual void NotifyModifyAttempt(Document *doc, void *userData) = 0;
 	virtual void NotifySavePoint(Document *doc, void *userData, bool atSavePoint) = 0;
 	virtual void NotifyModified(Document *doc, DocModification mh, void *userData) = 0;
-	virtual void NotifyDeleted(Document *doc, void *userData) = 0;
+	virtual void NotifyDeleted(Document *doc, void *userData) noexcept = 0;
 	virtual void NotifyStyleNeeded(Document *doc, void *userData, Sci::Position endPos) = 0;
 	virtual void NotifyLexerChanged(Document *doc, void *userData) = 0;
 	virtual void NotifyErrorOccurred(Document *doc, void *userData, int status) = 0;
diff --git a/scintilla/src/EditModel.cxx b/scintilla/src/EditModel.cxx
index 7ed7e350d0..99520f3cbd 100644
--- a/scintilla/src/EditModel.cxx
+++ b/scintilla/src/EditModel.cxx
@@ -24,6 +24,8 @@
 #include "ILexer.h"
 #include "Scintilla.h"
 
+#include "CharacterCategory.h"
+
 #include "Position.h"
 #include "UniqueString.h"
 #include "SplitVector.h"
@@ -75,3 +77,21 @@ EditModel::~EditModel() {
 	pdoc->Release();
 	pdoc = nullptr;
 }
+
+void EditModel::SetDefaultFoldDisplayText(const char *text) {
+	defaultFoldDisplayText = IsNullOrEmpty(text) ? UniqueString() : UniqueStringCopy(text);
+}
+
+const char *EditModel::GetDefaultFoldDisplayText() const noexcept {
+	return defaultFoldDisplayText.get();
+}
+
+const char *EditModel::GetFoldDisplayText(Sci::Line lineDoc) const {
+	if (foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN || pcs->GetExpanded(lineDoc)) {
+		return nullptr;
+	}
+
+	const char *text = pcs->GetFoldDisplayText(lineDoc);
+	return text ? text : defaultFoldDisplayText.get();
+}
+
diff --git a/scintilla/src/EditModel.h b/scintilla/src/EditModel.h
index da89c91988..ab5c23cdb9 100644
--- a/scintilla/src/EditModel.h
+++ b/scintilla/src/EditModel.h
@@ -40,6 +40,7 @@ class EditModel {
 
 	int foldFlags;
 	int foldDisplayTextStyle;
+	UniqueString defaultFoldDisplayText;
 	std::unique_ptr<IContractionState> pcs;
 	// Hotspot support
 	Range hotspot;
@@ -60,7 +61,10 @@ class EditModel {
 	virtual Sci::Line TopLineOfMain() const = 0;
 	virtual Point GetVisibleOriginInMain() const = 0;
 	virtual Sci::Line LinesOnScreen() const = 0;
-	virtual Range GetHotSpotRange() const = 0;
+	virtual Range GetHotSpotRange() const noexcept = 0;
+	void SetDefaultFoldDisplayText(const char *text);
+	const char *GetDefaultFoldDisplayText() const noexcept;
+	const char *GetFoldDisplayText(Sci::Line lineDoc) const;
 };
 
 }
diff --git a/scintilla/src/EditView.cxx b/scintilla/src/EditView.cxx
index 29ff925011..fa01a03856 100644
--- a/scintilla/src/EditView.cxx
+++ b/scintilla/src/EditView.cxx
@@ -9,7 +9,6 @@
 #include <cstdlib>
 #include <cassert>
 #include <cstring>
-#include <cctype>
 #include <cstdio>
 #include <cmath>
 
@@ -31,6 +30,7 @@
 
 #include "StringCopy.h"
 #include "CharacterSet.h"
+#include "CharacterCategory.h"
 #include "Position.h"
 #include "IntegerRectangle.h"
 #include "UniqueString.h"
@@ -64,7 +64,7 @@ static inline bool IsControlCharacter(int ch) {
 	return ch >= 0 && ch < ' ';
 }
 
-PrintParameters::PrintParameters() {
+PrintParameters::PrintParameters() noexcept {
 	magnification = 0;
 	colourMode = SC_PRINT_NORMAL;
 	wrapState = eWrapWord;
@@ -194,25 +194,25 @@ EditView::EditView() {
 EditView::~EditView() {
 }
 
-bool EditView::SetTwoPhaseDraw(bool twoPhaseDraw) {
+bool EditView::SetTwoPhaseDraw(bool twoPhaseDraw) noexcept {
 	const PhasesDraw phasesDrawNew = twoPhaseDraw ? phasesTwo : phasesOne;
 	const bool redraw = phasesDraw != phasesDrawNew;
 	phasesDraw = phasesDrawNew;
 	return redraw;
 }
 
-bool EditView::SetPhasesDraw(int phases) {
+bool EditView::SetPhasesDraw(int phases) noexcept {
 	const PhasesDraw phasesDrawNew = static_cast<PhasesDraw>(phases);
 	const bool redraw = phasesDraw != phasesDrawNew;
 	phasesDraw = phasesDrawNew;
 	return redraw;
 }
 
-bool EditView::LinesOverlap() const {
+bool EditView::LinesOverlap() const noexcept {
 	return phasesDraw == phasesMultiple;
 }
 
-void EditView::ClearAllTabstops() {
+void EditView::ClearAllTabstops() noexcept {
 	ldTabstops.reset();
 }
 
@@ -280,7 +280,7 @@ void EditView::AllocateGraphics(const ViewStyle &vsDraw) {
 		pixmapIndentGuideHighlight.reset(Surface::Allocate(vsDraw.technology));
 }
 
-static const char *ControlCharacterString(unsigned char ch) {
+static const char *ControlCharacterString(unsigned char ch) noexcept {
 	const char * const reps[] = {
 		"NUL", "SOH", "STX", "ETX", "EOT", "ENQ", "ACK", "BEL",
 		"BS", "HT", "LF", "VT", "FF", "CR", "SO", "SI",
@@ -649,7 +649,7 @@ Range EditView::RangeDisplayLine(Surface *surface, const EditModel &model, Sci::
 
 SelectionPosition EditView::SPositionFromLocation(Surface *surface, const EditModel &model, PointDocument pt, bool canReturnInvalid, bool charPosition, bool virtualSpace, const ViewStyle &vs) {
 	pt.x = pt.x - vs.textStart;
-	Sci::Line visibleLine = static_cast<int>(floor(pt.y / vs.lineHeight));
+	Sci::Line visibleLine = static_cast<int>(std::floor(pt.y / vs.lineHeight));
 	if (!canReturnInvalid && (visibleLine < 0))
 		visibleLine = 0;
 	const Sci::Line lineDoc = model.pcs->DocFromDisplay(visibleLine);
@@ -763,7 +763,7 @@ Sci::Position EditView::StartEndDisplayLine(Surface *surface, const EditModel &m
 	return posRet;
 }
 
-static ColourDesired SelectionBackground(const ViewStyle &vsDraw, bool main, bool primarySelection) {
+static ColourDesired SelectionBackground(const ViewStyle &vsDraw, bool main, bool primarySelection) noexcept {
 	return main ?
 		(primarySelection ? vsDraw.selColours.back : vsDraw.selBackground2) :
 		vsDraw.selAdditionalBackground;
@@ -816,7 +816,7 @@ static void DrawTextBlob(Surface *surface, const ViewStyle &vsDraw, PRectangle r
 		surface->FillRectangle(rcSegment, textBack);
 	}
 	FontAlias ctrlCharsFont = vsDraw.styles[STYLE_CONTROLCHAR].font;
-	const int normalCharHeight = static_cast<int>(ceil(vsDraw.styles[STYLE_CONTROLCHAR].capitalHeight));
+	const int normalCharHeight = static_cast<int>(std::ceil(vsDraw.styles[STYLE_CONTROLCHAR].capitalHeight));
 	PRectangle rcCChar = rcSegment;
 	rcCChar.left = rcCChar.left + 1;
 	rcCChar.top = rcSegment.top + vsDraw.maxAscent - normalCharHeight;
@@ -985,7 +985,7 @@ void EditView::DrawEOL(Surface *surface, const EditModel &model, const ViewStyle
 		rcSegment.left = rcLine.left;
 	rcSegment.right = rcLine.right;
 
-	const bool fillRemainder = !lastSubLine || model.foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN || !model.pcs->GetFoldDisplayTextShown(line);
+	const bool fillRemainder = !lastSubLine || !model.GetFoldDisplayText(line);
 	if (fillRemainder) {
 		// Fill the remainder of the line
 		FillLineRemainder(surface, model, vsDraw, ll, line, rcSegment, subLine);
@@ -1105,11 +1105,12 @@ void EditView::DrawFoldDisplayText(Surface *surface, const EditModel &model, con
 	if (!lastSubLine)
 		return;
 
-	if ((model.foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN) || !model.pcs->GetFoldDisplayTextShown(line))
+	const char *text = model.GetFoldDisplayText(line);
+	if (!text)
 		return;
 
 	PRectangle rcSegment = rcLine;
-	const char *foldDisplayText = model.pcs->GetFoldDisplayText(line);
+	const char *foldDisplayText = text;
 	const int lengthFoldDisplayText = static_cast<int>(strlen(foldDisplayText));
 	FontAlias fontText = vsDraw.styles[STYLE_FOLDDISPLAYTEXT].font;
 	const int widthFoldDisplayText = static_cast<int>(surface->WidthText(fontText, foldDisplayText, lengthFoldDisplayText));
@@ -1129,7 +1130,6 @@ void EditView::DrawFoldDisplayText(Surface *surface, const EditModel &model, con
 	rcSegment.right = rcSegment.left + static_cast<XYPOSITION>(widthFoldDisplayText);
 
 	const ColourOptional background = vsDraw.Background(model.pdoc->GetMark(line), model.caret.active, ll->containsCaret);
-	FontAlias textFont = vsDraw.styles[STYLE_FOLDDISPLAYTEXT].font;
 	ColourDesired textFore = vsDraw.styles[STYLE_FOLDDISPLAYTEXT].fore;
 	if (eolInSelection && (vsDraw.selColours.fore.isSet)) {
 		textFore = (eolInSelection == 1) ? vsDraw.selColours.fore : vsDraw.selAdditionalForeground;
@@ -1158,11 +1158,11 @@ void EditView::DrawFoldDisplayText(Surface *surface, const EditModel &model, con
 
 	if (phase & drawText) {
 		if (phasesDraw != phasesOne) {
-			surface->DrawTextTransparent(rcSegment, textFont,
+			surface->DrawTextTransparent(rcSegment, fontText,
 				rcSegment.top + vsDraw.maxAscent, foldDisplayText,
 				lengthFoldDisplayText, textFore);
 		} else {
-			surface->DrawTextNoClip(rcSegment, textFont,
+			surface->DrawTextNoClip(rcSegment, fontText,
 				rcSegment.top + vsDraw.maxAscent, foldDisplayText,
 				lengthFoldDisplayText, textFore, textBack);
 		}
@@ -1332,7 +1332,7 @@ void EditView::DrawCarets(Surface *surface, const EditModel &model, const ViewSt
 	for (size_t r = 0; (r<model.sel.Count()) || drawDrag; r++) {
 		const bool mainCaret = r == model.sel.Main();
 		SelectionPosition posCaret = (drawDrag ? model.posDrag : model.sel.Range(r).caret);
-		if (vsDraw.caretStyle == CARETSTYLE_BLOCK && !drawDrag && posCaret > model.sel.Range(r).anchor) {
+		if ((vsDraw.IsBlockCaretStyle() || imeCaretBlockOverride) && !drawDrag && posCaret > model.sel.Range(r).anchor) {
 			if (posCaret.VirtualSpace() > 0)
 				posCaret.SetVirtualSpace(posCaret.VirtualSpace() - 1);
 			else
@@ -1351,7 +1351,7 @@ void EditView::DrawCarets(Surface *surface, const EditModel &model, const ViewSt
 			const bool caretBlinkState = (model.caret.active && model.caret.on) || (!additionalCaretsBlink && !mainCaret);
 			const bool caretVisibleState = additionalCaretsVisible || mainCaret;
 			if ((xposCaret >= 0) && (vsDraw.caretWidth > 0) && (vsDraw.caretStyle != CARETSTYLE_INVISIBLE) &&
-				((model.posDrag.IsValid()) || (caretBlinkState && caretVisibleState))) {
+				(drawDrag || (caretBlinkState && caretVisibleState))) {
 				bool caretAtEOF = false;
 				bool caretAtEOL = false;
 				bool drawBlockCaret = false;
@@ -1375,16 +1375,17 @@ void EditView::DrawCarets(Surface *surface, const EditModel &model, const ViewSt
 				if (xposCaret > 0)
 					caretWidthOffset = 0.51f;	// Move back so overlaps both character cells.
 				xposCaret += xStart;
-				if (model.posDrag.IsValid()) {
+				const ViewStyle::CaretShape caretShape = drawDrag ? ViewStyle::CaretShape::line : vsDraw.CaretShapeForMode(model.inOverstrike);
+				if (drawDrag) {
 					/* Dragging text, use a line caret */
 					rcCaret.left = round(xposCaret - caretWidthOffset);
 					rcCaret.right = rcCaret.left + vsDraw.caretWidth;
-				} else if (model.inOverstrike && drawOverstrikeCaret) {
+				} else if ((caretShape == ViewStyle::CaretShape::bar) && drawOverstrikeCaret) {
 					/* Overstrike (insert mode), use a modified bar caret */
 					rcCaret.top = rcCaret.bottom - 2;
 					rcCaret.left = xposCaret + 1;
 					rcCaret.right = rcCaret.left + widthOverstrikeCaret - 1;
-				} else if ((vsDraw.caretStyle == CARETSTYLE_BLOCK) || imeCaretBlockOverride) {
+				} else if ((caretShape == ViewStyle::CaretShape::block) || imeCaretBlockOverride) {
 					/* Block caret */
 					rcCaret.left = xposCaret;
 					if (!caretAtEOL && !caretAtEOF && (ll->chars[offset] != '\t') && !(IsControlCharacter(ll->chars[offset]))) {
@@ -1711,7 +1712,7 @@ void EditView::DrawForeground(Surface *surface, const EditModel &model, const Vi
 							indentCount <= (ll->positions[i + 1] - epsilon) / indentWidth;
 							indentCount++) {
 							if (indentCount > 0) {
-								const XYPOSITION xIndent = floor(indentCount * indentWidth);
+								const XYPOSITION xIndent = std::floor(indentCount * indentWidth);
 								DrawIndentGuide(surface, lineVisible, vsDraw.lineHeight, xIndent + xStart, rcSegment,
 									(ll->xHighlightGuide == xIndent));
 							}
@@ -1791,7 +1792,7 @@ void EditView::DrawForeground(Surface *surface, const EditModel &model, const Vi
 									indentCount <= (ll->positions[cpos + ts.start + 1] - epsilon) / indentWidth;
 									indentCount++) {
 									if (indentCount > 0) {
-										const XYPOSITION xIndent = floor(indentCount * indentWidth);
+										const XYPOSITION xIndent = std::floor(indentCount * indentWidth);
 										DrawIndentGuide(surface, lineVisible, vsDraw.lineHeight, xIndent + xStart, rcSegment,
 											(ll->xHighlightGuide == xIndent));
 									}
@@ -1868,7 +1869,7 @@ void EditView::DrawIndentGuidesOverEmpty(Surface *surface, const EditModel &mode
 		}
 
 		for (int indentPos = model.pdoc->IndentSize(); indentPos < indentSpace; indentPos += model.pdoc->IndentSize()) {
-			const XYPOSITION xIndent = floor(indentPos * vsDraw.spaceWidth);
+			const XYPOSITION xIndent = std::floor(indentPos * vsDraw.spaceWidth);
 			if (xIndent < xStartText) {
 				DrawIndentGuide(surface, lineVisible, vsDraw.lineHeight, xIndent + xStart, rcLine,
 					(ll->xHighlightGuide == xIndent));
@@ -2198,7 +2199,7 @@ void EditView::FillLineRemainder(Surface *surface, const EditModel &model, const
 // Space (3 space characters) between line numbers and text when printing.
 #define lineNumberPrintSpace "   "
 
-static ColourDesired InvertedLight(ColourDesired orig) {
+static ColourDesired InvertedLight(ColourDesired orig) noexcept {
 	unsigned int r = orig.GetRed();
 	unsigned int g = orig.GetGreen();
 	unsigned int b = orig.GetBlue();
diff --git a/scintilla/src/EditView.h b/scintilla/src/EditView.h
index f649f7c872..3addfbab8e 100644
--- a/scintilla/src/EditView.h
+++ b/scintilla/src/EditView.h
@@ -14,7 +14,7 @@ struct PrintParameters {
 	int magnification;
 	int colourMode;
 	WrapMode wrapState;
-	PrintParameters();
+	PrintParameters() noexcept;
 };
 
 /**
@@ -54,7 +54,7 @@ class EditView {
 	int tabWidthMinimumPixels;
 
 	bool hideSelection;
-	bool drawOverstrikeCaret;
+	bool drawOverstrikeCaret; // used by the curses platform
 
 	/** In bufferedDraw mode, graphics operations are drawn to a pixmap and then copied to
 	* the screen. This avoids flashing but is about 30% slower. */
@@ -97,11 +97,11 @@ class EditView {
 	void operator=(EditView &&) = delete;
 	virtual ~EditView();
 
-	bool SetTwoPhaseDraw(bool twoPhaseDraw);
-	bool SetPhasesDraw(int phases);
-	bool LinesOverlap() const;
+	bool SetTwoPhaseDraw(bool twoPhaseDraw) noexcept;
+	bool SetPhasesDraw(int phases) noexcept;
+	bool LinesOverlap() const noexcept;
 
-	void ClearAllTabstops();
+	void ClearAllTabstops() noexcept;
 	XYPOSITION NextTabstopPos(Sci::Line line, XYPOSITION x, XYPOSITION tabWidth) const;
 	bool ClearTabstops(Sci::Line line);
 	bool AddTabstop(Sci::Line line, int x);
@@ -165,7 +165,7 @@ class AutoLineLayout {
 	AutoLineLayout(AutoLineLayout &&) = delete;
 	AutoLineLayout &operator=(const AutoLineLayout &) = delete;
 	AutoLineLayout &operator=(AutoLineLayout &&) = delete;
-	~AutoLineLayout() {
+	~AutoLineLayout() noexcept {
 		llc.Dispose(ll);
 		ll = nullptr;
 	}
@@ -175,7 +175,7 @@ class AutoLineLayout {
 	operator LineLayout *() const noexcept {
 		return ll;
 	}
-	void Set(LineLayout *ll_) {
+	void Set(LineLayout *ll_) noexcept {
 		llc.Dispose(ll);
 		ll = ll_;
 	}
diff --git a/scintilla/src/Editor.cxx b/scintilla/src/Editor.cxx
index 7e5be38dff..8f583636d6 100644
--- a/scintilla/src/Editor.cxx
+++ b/scintilla/src/Editor.cxx
@@ -9,7 +9,6 @@
 #include <cstdlib>
 #include <cassert>
 #include <cstring>
-#include <cctype>
 #include <cstdio>
 #include <cmath>
 
@@ -31,6 +30,7 @@
 
 #include "StringCopy.h"
 #include "CharacterSet.h"
+#include "CharacterCategory.h"
 #include "Position.h"
 #include "UniqueString.h"
 #include "SplitVector.h"
@@ -59,11 +59,13 @@
 
 using namespace Scintilla;
 
+namespace {
+
 /*
 	return whether this modification represents an operation that
 	may reasonably be deferred (not done now OR [possibly] at all)
 */
-static bool CanDeferToLastStep(const DocModification &mh) {
+bool CanDeferToLastStep(const DocModification &mh) noexcept {
 	if (mh.modificationType & (SC_MOD_BEFOREINSERT | SC_MOD_BEFOREDELETE))
 		return true;	// CAN skip
 	if (!(mh.modificationType & (SC_PERFORMED_UNDO | SC_PERFORMED_REDO)))
@@ -73,7 +75,7 @@ static bool CanDeferToLastStep(const DocModification &mh) {
 	return false;		// PRESUMABLY must do
 }
 
-static bool CanEliminate(const DocModification &mh) {
+constexpr bool CanEliminate(const DocModification &mh) noexcept {
 	return
 	    (mh.modificationType & (SC_MOD_BEFOREINSERT | SC_MOD_BEFOREDELETE)) != 0;
 }
@@ -82,7 +84,7 @@ static bool CanEliminate(const DocModification &mh) {
 	return whether this modification represents the FINAL step
 	in a [possibly lengthy] multi-step Undo/Redo sequence
 */
-static bool IsLastStep(const DocModification &mh) {
+constexpr bool IsLastStep(const DocModification &mh) noexcept {
 	return
 	    (mh.modificationType & (SC_PERFORMED_UNDO | SC_PERFORMED_REDO)) != 0
 	    && (mh.modificationType & SC_MULTISTEPUNDOREDO) != 0
@@ -90,13 +92,15 @@ static bool IsLastStep(const DocModification &mh) {
 	    && (mh.modificationType & SC_MULTILINEUNDOREDO) != 0;
 }
 
-Timer::Timer() :
+}
+
+Timer::Timer() noexcept :
 		ticking(false), ticksToWait(0), tickerID{} {}
 
-Idler::Idler() :
+Idler::Idler() noexcept :
 		state(false), idlerID(0) {}
 
-static inline bool IsAllSpacesOrTabs(const char *s, unsigned int len) {
+static bool IsAllSpacesOrTabs(const char *s, unsigned int len) noexcept {
 	for (unsigned int i = 0; i < len; i++) {
 		// This is safe because IsSpaceOrTab() will return false for null terminators
 		if (!IsSpaceOrTab(s[i]))
@@ -1144,13 +1148,9 @@ slop | strict | jumps | even | Caret can go to the margin                 | When
 
 Editor::XYScrollPosition Editor::XYScrollToMakeVisible(const SelectionRange &range, const XYScrollOptions options) {
 	const PRectangle rcClient = GetTextRectangle();
-	Point pt = LocationFromPosition(range.caret);
-	Point ptAnchor = LocationFromPosition(range.anchor);
 	const Point ptOrigin = GetVisibleOriginInMain();
-	pt.x += ptOrigin.x;
-	pt.y += ptOrigin.y;
-	ptAnchor.x += ptOrigin.x;
-	ptAnchor.y += ptOrigin.y;
+	const Point pt = LocationFromPosition(range.caret) + ptOrigin;
+	const Point ptAnchor = LocationFromPosition(range.anchor) + ptOrigin;
 	const Point ptBottomCaret(pt.x, pt.y + vs.lineHeight - 1);
 
 	XYScrollPosition newXY(xOffset, topLine);
@@ -1355,7 +1355,7 @@ Editor::XYScrollPosition Editor::XYScrollToMakeVisible(const SelectionRange &ran
 			newXY.xOffset = static_cast<int>(pt.x + xOffset - rcClient.left) - 2;
 		} else if (pt.x + xOffset >= rcClient.right + newXY.xOffset) {
 			newXY.xOffset = static_cast<int>(pt.x + xOffset - rcClient.right) + 2;
-			if ((vs.caretStyle == CARETSTYLE_BLOCK) || view.imeCaretBlockOverride) {
+			if (vs.IsBlockCaretStyle() || view.imeCaretBlockOverride) {
 				// Ensure we can see a good portion of the block caret
 				newXY.xOffset += static_cast<int>(vs.aveCharWidth);
 			}
@@ -1465,7 +1465,7 @@ void Editor::NotifyCaretMove() {
 void Editor::UpdateSystemCaret() {
 }
 
-bool Editor::Wrapping() const {
+bool Editor::Wrapping() const noexcept {
 	return vs.wrapState != eWrapNone;
 }
 
@@ -1614,7 +1614,7 @@ void Editor::LinesJoin() {
 	}
 }
 
-const char *Editor::StringFromEOLMode(int eolMode) {
+const char *Editor::StringFromEOLMode(int eolMode) noexcept {
 	if (eolMode == SC_EOL_CRLF) {
 		return "\r\n";
 	} else if (eolMode == SC_EOL_CR) {
@@ -1900,6 +1900,9 @@ void Editor::FilterSelections() {
 
 // AddCharUTF inserts an array of bytes which may or may not be in UTF-8.
 void Editor::AddCharUTF(const char *s, unsigned int len, bool treatAsDBCS) {
+	if (len == 0) {
+		return;
+	}
 	FilterSelections();
 	{
 		UndoGroup ug(pdoc, (sel.Count() > 1) || !sel.Empty() || inOverstrike);
@@ -1970,12 +1973,14 @@ void Editor::AddCharUTF(const char *s, unsigned int len, bool treatAsDBCS) {
 		SetLastXChosen();
 	}
 
-	if (treatAsDBCS) {
-		NotifyChar((static_cast<unsigned char>(s[0]) << 8) |
-		        static_cast<unsigned char>(s[1]));
-	} else if (len > 0) {
-		int byte = static_cast<unsigned char>(s[0]);
-		if ((byte < 0xC0) || (1 == len)) {
+	int ch = static_cast<unsigned char>(s[0]);
+	if (treatAsDBCS || pdoc->dbcsCodePage != SC_CP_UTF8) {
+		if (len > 1) {
+			// DBCS code page or DBCS font character set.
+			ch = (ch << 8) | static_cast<unsigned char>(s[1]);
+		}
+	} else {
+		if ((ch < 0xC0) || (1 == len)) {
 			// Handles UTF-8 characters between 0x01 and 0x7F and single byte
 			// characters when not in UTF-8 mode.
 			// Also treats \0 and naked trail bytes 0x80 to 0xBF as valid
@@ -1983,10 +1988,10 @@ void Editor::AddCharUTF(const char *s, unsigned int len, bool treatAsDBCS) {
 		} else {
 			unsigned int utf32[1] = { 0 };
 			UTF32FromUTF8(s, len, utf32, ELEMENTS(utf32));
-			byte = utf32[0];
+			ch = utf32[0];
 		}
-		NotifyChar(byte);
 	}
+	NotifyChar(ch);
 
 	if (recordingMacro) {
 		NotifyMacroRecord(SCI_REPLACESEL, 0, reinterpret_cast<sptr_t>(s));
@@ -2521,8 +2526,10 @@ void Editor::CheckModificationForWrap(DocModification mh) {
 	}
 }
 
+namespace {
+
 // Move a position so it is still after the same character as before the insertion.
-static inline Sci::Position MovePositionForInsertion(Sci::Position position, Sci::Position startInsertion, Sci::Position length) {
+Sci::Position MovePositionForInsertion(Sci::Position position, Sci::Position startInsertion, Sci::Position length) noexcept {
 	if (position > startInsertion) {
 		return position + length;
 	}
@@ -2531,7 +2538,7 @@ static inline Sci::Position MovePositionForInsertion(Sci::Position position, Sci
 
 // Move a position so it is still after the same character as before the deletion if that
 // character is still present else after the previous surviving character.
-static inline Sci::Position MovePositionForDeletion(Sci::Position position, Sci::Position startDeletion, Sci::Position length) {
+Sci::Position MovePositionForDeletion(Sci::Position position, Sci::Position startDeletion, Sci::Position length) noexcept {
 	if (position > startDeletion) {
 		const Sci::Position endDeletion = startDeletion + length;
 		if (position > endDeletion) {
@@ -2544,6 +2551,8 @@ static inline Sci::Position MovePositionForDeletion(Sci::Position position, Sci:
 	}
 }
 
+}
+
 void Editor::NotifyModified(Document *, DocModification mh, void *) {
 	ContainerNeedsUpdate(SC_UPDATE_CONTENT);
 	if (paintState == painting) {
@@ -2652,12 +2661,16 @@ void Editor::NotifyModified(Document *, DocModification mh, void *) {
 			}
 
 			if (paintState == notPainting && !CanDeferToLastStep(mh)) {
-				QueueIdleWork(WorkNeeded::workStyle, pdoc->Length());
+				if (SynchronousStylingToVisible()) {
+					QueueIdleWork(WorkNeeded::workStyle, pdoc->Length());
+				}
 				Redraw();
 			}
 		} else {
 			if (paintState == notPainting && mh.length && !CanEliminate(mh)) {
-				QueueIdleWork(WorkNeeded::workStyle, mh.position + mh.length);
+				if (SynchronousStylingToVisible()) {
+					QueueIdleWork(WorkNeeded::workStyle, mh.position + mh.length);
+				}
 				InvalidateRange(mh.position, mh.position + mh.length);
 			}
 		}
@@ -2712,7 +2725,7 @@ void Editor::NotifyModified(Document *, DocModification mh, void *) {
 	}
 }
 
-void Editor::NotifyDeleted(Document *, void *) {
+void Editor::NotifyDeleted(Document *, void *) noexcept {
 	/* Do nothing */
 }
 
@@ -2848,7 +2861,7 @@ void Editor::NotifyMacroRecord(unsigned int iMessage, uptr_t wParam, sptr_t lPar
 }
 
 // Something has changed that the container should know about
-void Editor::ContainerNeedsUpdate(int flags) {
+void Editor::ContainerNeedsUpdate(int flags) noexcept {
 	needUpdateUI |= flags;
 }
 
@@ -3232,7 +3245,7 @@ constexpr short LowShortFromWParam(uptr_t x) {
 	return static_cast<short>(x & 0xffff);
 }
 
-unsigned int WithExtends(unsigned int iMessage) {
+unsigned int WithExtends(unsigned int iMessage) noexcept {
 	switch (iMessage) {
 	case SCI_CHARLEFT: return SCI_CHARLEFTEXTEND;
 	case SCI_CHARRIGHT: return SCI_CHARRIGHTEXTEND;
@@ -3259,7 +3272,7 @@ unsigned int WithExtends(unsigned int iMessage) {
 	}
 }
 
-int NaturalDirection(unsigned int iMessage) {
+int NaturalDirection(unsigned int iMessage) noexcept {
 	switch (iMessage) {
 	case SCI_CHARLEFT:
 	case SCI_CHARLEFTEXTEND:
@@ -3290,7 +3303,7 @@ int NaturalDirection(unsigned int iMessage) {
 	}
 }
 
-bool IsRectExtend(unsigned int iMessage, bool isRectMoveExtends) {
+bool IsRectExtend(unsigned int iMessage, bool isRectMoveExtends) noexcept {
 	switch (iMessage) {
 	case SCI_CHARLEFTRECTEXTEND:
 	case SCI_CHARRIGHTRECTEXTEND:
@@ -3793,6 +3806,7 @@ int Editor::KeyCommand(unsigned int iMessage) {
 		inOverstrike = !inOverstrike;
 		ContainerNeedsUpdate(SC_UPDATE_SELECTION);
 		ShowCaretAtCurrentPosition();
+		SetIdle(true);
 		break;
 	case SCI_CANCEL:            	// Cancel any modes - handled in subclass
 		// Also unselect text
@@ -4015,11 +4029,9 @@ void Editor::Indent(bool forwards) {
 
 class CaseFolderASCII : public CaseFolderTable {
 public:
-	CaseFolderASCII() {
+	CaseFolderASCII() noexcept {
 		StandardASCII();
 	}
-	~CaseFolderASCII() override {
-	}
 };
 
 
@@ -4160,10 +4172,11 @@ void Editor::GoToLine(Sci::Line lineNo) {
 	EnsureCaretVisible();
 }
 
-static bool Close(Point pt1, Point pt2, Point threshold) {
-	if (std::abs(pt1.x - pt2.x) > threshold.x)
+static bool Close(Point pt1, Point pt2, Point threshold) noexcept {
+	const Point ptDifference = pt2 - pt1;
+	if (std::abs(ptDifference.x) > threshold.x)
 		return false;
-	if (std::abs(pt1.y - pt2.y) > threshold.y)
+	if (std::abs(ptDifference.y) > threshold.y)
 		return false;
 	return true;
 }
@@ -4253,9 +4266,8 @@ void Editor::DisplayCursor(Window::Cursor c) {
 }
 
 bool Editor::DragThreshold(Point ptStart, Point ptNow) {
-	const XYPOSITION xMove = ptStart.x - ptNow.x;
-	const XYPOSITION yMove = ptStart.y - ptNow.y;
-	const XYPOSITION distanceSquared = xMove * xMove + yMove * yMove;
+	const Point ptDiff = ptStart - ptNow;
+	const XYPOSITION distanceSquared = ptDiff.x * ptDiff.x + ptDiff.y * ptDiff.y;
 	return distanceSquared > 16.0f;
 }
 
@@ -4383,7 +4395,7 @@ bool Editor::PointInSelMargin(Point pt) const {
 	}
 }
 
-Window::Cursor Editor::GetMarginCursor(Point pt) const {
+Window::Cursor Editor::GetMarginCursor(Point pt) const noexcept {
 	int x = 0;
 	for (const MarginStyle &m : vs.ms) {
 		if ((pt.x >= x) && (pt.x < x + m.width))
@@ -4730,12 +4742,12 @@ void Editor::SetHotSpotRange(const Point *pt) {
 	}
 }
 
-Range Editor::GetHotSpotRange() const {
+Range Editor::GetHotSpotRange() const noexcept {
 	return hotspot;
 }
 
 void Editor::ButtonMoveWithModifiers(Point pt, unsigned int, int modifiers) {
-	if ((ptMouseLast.x != pt.x) || (ptMouseLast.y != pt.y)) {
+	if (ptMouseLast != pt) {
 		DwellEnd(true);
 	}
 
@@ -4948,6 +4960,8 @@ void Editor::ButtonUpWithModifiers(Point pt, unsigned int curTime, int modifiers
 }
 
 bool Editor::Idle() {
+	NotifyUpdateUI();
+
 	bool needWrap = Wrapping() && wrapPending.NeedsWrap();
 
 	if (needWrap) {
@@ -5057,7 +5071,7 @@ void Editor::StyleToPositionInView(Sci::Position pos) {
 }
 
 Sci::Position Editor::PositionAfterMaxStyling(Sci::Position posMax, bool scrolling) const {
-	if ((idleStyling == SC_IDLESTYLING_NONE) || (idleStyling == SC_IDLESTYLING_AFTERVISIBLE)) {
+	if (SynchronousStylingToVisible()) {
 		// Both states do not limit styling
 		return posMax;
 	}
@@ -5570,11 +5584,11 @@ Sci::Position Editor::ReplaceTarget(bool replacePatterns, const char *text, Sci:
 	return length;
 }
 
-bool Editor::IsUnicodeMode() const {
+bool Editor::IsUnicodeMode() const noexcept {
 	return pdoc && (SC_CP_UTF8 == pdoc->dbcsCodePage);
 }
 
-int Editor::CodePage() const {
+int Editor::CodePage() const noexcept {
 	if (pdoc)
 		return pdoc->dbcsCodePage;
 	else
@@ -5610,7 +5624,7 @@ void Editor::AddStyledText(const char *buffer, Sci::Position appendLength) {
 	SetEmptySelection(sel.MainCaret() + lengthInserted);
 }
 
-bool Editor::ValidMargin(uptr_t wParam) const {
+bool Editor::ValidMargin(uptr_t wParam) const noexcept {
 	return wParam < vs.ms.size();
 }
 
@@ -5739,7 +5753,7 @@ void Editor::SetSelectionNMessage(unsigned int iMessage, uptr_t wParam, sptr_t l
 	ContainerNeedsUpdate(SC_UPDATE_SELECTION);
 }
 
-sptr_t Editor::StringResult(sptr_t lParam, const char *val) {
+sptr_t Editor::StringResult(sptr_t lParam, const char *val) noexcept {
 	const size_t len = val ? strlen(val) : 0;
 	if (lParam) {
 		char *ptr = CharPtrFromSPtr(lParam);
@@ -5751,7 +5765,7 @@ sptr_t Editor::StringResult(sptr_t lParam, const char *val) {
 	return len;	// Not including NUL
 }
 
-sptr_t Editor::BytesResult(sptr_t lParam, const unsigned char *val, size_t len) {
+sptr_t Editor::BytesResult(sptr_t lParam, const unsigned char *val, size_t len) noexcept {
 	// No NUL termination: len is number of valid/displayed bytes
 	if ((lParam) && (len > 0)) {
 		char *ptr = CharPtrFromSPtr(lParam);
@@ -6240,6 +6254,13 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 		pdoc->SetDefaultCharClasses(true);
 		break;
 
+	case SCI_SETCHARACTERCATEGORYOPTIMIZATION:
+		pdoc->SetCharacterCategoryOptimization(static_cast<int>(wParam));
+		break;
+
+	case SCI_GETCHARACTERCATEGORYOPTIMIZATION:
+		return pdoc->CharacterCategoryOptimization();
+
 	case SCI_GETLENGTH:
 		return pdoc->Length();
 
@@ -7172,6 +7193,17 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 		Redraw();
 		break;
 
+	case SCI_FOLDDISPLAYTEXTGETSTYLE:
+		return foldDisplayTextStyle;
+
+	case SCI_SETDEFAULTFOLDDISPLAYTEXT:
+		SetDefaultFoldDisplayText(CharPtrFromSPtr(lParam));
+		Redraw();
+		break;
+
+	case SCI_GETDEFAULTFOLDDISPLAYTEXT:
+		return StringResult(lParam, GetDefaultFoldDisplayText());
+
 	case SCI_TOGGLEFOLD:
 		FoldLine(static_cast<Sci::Line>(wParam), SC_FOLDACTION_TOGGLE);
 		break;
@@ -7281,7 +7313,7 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 		return vs.caretcolour.AsInteger();
 
 	case SCI_SETCARETSTYLE:
-		if (wParam <= CARETSTYLE_BLOCK)
+		if (wParam <= (CARETSTYLE_BLOCK | CARETSTYLE_OVERSTRIKE_BLOCK))
 			vs.caretStyle = static_cast<int>(wParam);
 		else
 			/* Default to the line caret */
@@ -7736,6 +7768,7 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 			inOverstrike = wParam != 0;
 			ContainerNeedsUpdate(SC_UPDATE_SELECTION);
 			ShowCaretAtCurrentPosition();
+			SetIdle(true);
 		}
 		break;
 
diff --git a/scintilla/src/Editor.h b/scintilla/src/Editor.h
index 55b6f56aa2..e8d1ed48e4 100644
--- a/scintilla/src/Editor.h
+++ b/scintilla/src/Editor.h
@@ -19,7 +19,7 @@ class Timer {
 	enum {tickSize = 100};
 	TickerID tickerID;
 
-	Timer();
+	Timer() noexcept;
 };
 
 /**
@@ -29,7 +29,7 @@ class Idler {
 	bool state;
 	IdlerID idlerID;
 
-	Idler();
+	Idler() noexcept;
 };
 
 /**
@@ -47,12 +47,12 @@ class WorkNeeded {
 	enum workItems items;
 	Sci::Position upTo;
 
-	WorkNeeded() : items(workNone), upTo(0) {}
-	void Reset() {
+	WorkNeeded() noexcept : items(workNone), upTo(0) {}
+	void Reset() noexcept {
 		items = workNone;
 		upTo = 0;
 	}
-	void Need(workItems items_, Sci::Position pos) {
+	void Need(workItems items_, Sci::Position pos) noexcept {
 		if ((items_ & workStyle) && (upTo < pos))
 			upTo = pos;
 		items = static_cast<workItems>(items | items_);
@@ -69,8 +69,8 @@ class SelectionText {
 	bool lineCopy;
 	int codePage;
 	int characterSet;
-	SelectionText() : rectangular(false), lineCopy(false), codePage(0), characterSet(0) {}
-	void Clear() {
+	SelectionText() noexcept : rectangular(false), lineCopy(false), codePage(0), characterSet(0) {}
+	void Clear() noexcept {
 		s.clear();
 		rectangular = false;
 		lineCopy = false;
@@ -88,16 +88,16 @@ class SelectionText {
 	void Copy(const SelectionText &other) {
 		Copy(other.s, other.codePage, other.characterSet, other.rectangular, other.lineCopy);
 	}
-	const char *Data() const {
+	const char *Data() const noexcept {
 		return s.c_str();
 	}
-	size_t Length() const {
+	size_t Length() const noexcept {
 		return s.length();
 	}
-	size_t LengthWithTerminator() const {
+	size_t LengthWithTerminator() const noexcept {
 		return s.length() + 1;
 	}
-	bool Empty() const {
+	bool Empty() const noexcept {
 		return s.empty();
 	}
 private:
@@ -113,22 +113,22 @@ struct WrapPending {
 	enum { lineLarge = 0x7ffffff };
 	Sci::Line start;	// When there are wraps pending, will be in document range
 	Sci::Line end;	// May be lineLarge to indicate all of document after start
-	WrapPending() {
+	WrapPending() noexcept {
 		start = lineLarge;
 		end = lineLarge;
 	}
-	void Reset() {
+	void Reset() noexcept {
 		start = lineLarge;
 		end = lineLarge;
 	}
-	void Wrapped(Sci::Line line) {
+	void Wrapped(Sci::Line line) noexcept {
 		if (start == line)
 			start++;
 	}
-	bool NeedsWrap() const {
+	bool NeedsWrap() const noexcept {
 		return start < end;
 	}
-	bool AddRange(Sci::Line lineStart, Sci::Line lineEnd) {
+	bool AddRange(Sci::Line lineStart, Sci::Line lineEnd) noexcept {
 		const bool neededWrap = NeedsWrap();
 		bool changed = false;
 		if (start > lineStart) {
@@ -260,7 +260,7 @@ class Editor : public EditModel, public DocWatcher {
 	Editor(Editor &&) = delete;
 	Editor &operator=(const Editor &) = delete;
 	Editor &operator=(Editor &&) = delete;
-	~Editor() override;
+	// ~Editor() in public section
 	virtual void Initialise() = 0;
 	virtual void Finalise();
 
@@ -302,7 +302,7 @@ class Editor : public EditModel, public DocWatcher {
 	PRectangle RectangleFromRange(Range r, int overlap);
 	void InvalidateRange(Sci::Position start, Sci::Position end);
 
-	bool UserVirtualSpace() const {
+	bool UserVirtualSpace() const noexcept {
 		return ((virtualSpaceOptions & SCVS_USERACCESSIBLE) != 0);
 	}
 	Sci::Position CurrentPosition() const;
@@ -347,8 +347,8 @@ class Editor : public EditModel, public DocWatcher {
 	struct XYScrollPosition {
 		int xOffset;
 		Sci::Line topLine;
-		XYScrollPosition(int xOffset_, Sci::Line topLine_) : xOffset(xOffset_), topLine(topLine_) {}
-		bool operator==(const XYScrollPosition &other) const {
+		XYScrollPosition(int xOffset_, Sci::Line topLine_) noexcept : xOffset(xOffset_), topLine(topLine_) {}
+		bool operator==(const XYScrollPosition &other) const noexcept {
 			return (xOffset == other.xOffset) && (topLine == other.topLine);
 		}
 	};
@@ -368,7 +368,7 @@ class Editor : public EditModel, public DocWatcher {
 	virtual void NotifyCaretMove();
 	virtual void UpdateSystemCaret();
 
-	bool Wrapping() const;
+	bool Wrapping() const noexcept;
 	void NeedWrapping(Sci::Line docLineStart=0, Sci::Line docLineEnd=WrapPending::lineLarge);
 	bool WrapOneLine(Surface *surface, Sci::Line lineToWrap);
 	enum class WrapScope {wsAll, wsVisible, wsIdle};
@@ -441,13 +441,13 @@ class Editor : public EditModel, public DocWatcher {
 	void NotifySavePoint(Document *document, void *userData, bool atSavePoint) override;
 	void CheckModificationForWrap(DocModification mh);
 	void NotifyModified(Document *document, DocModification mh, void *userData) override;
-	void NotifyDeleted(Document *document, void *userData) override;
+	void NotifyDeleted(Document *document, void *userData) noexcept override;
 	void NotifyStyleNeeded(Document *doc, void *userData, Sci::Position endStyleNeeded) override;
 	void NotifyLexerChanged(Document *doc, void *userData) override;
 	void NotifyErrorOccurred(Document *doc, void *userData, int status) override;
 	void NotifyMacroRecord(unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 
-	void ContainerNeedsUpdate(int flags);
+	void ContainerNeedsUpdate(int flags) noexcept;
 	void PageMove(int direction, Selection::selTypes selt=Selection::noSel, bool stuttered = false);
 	enum { cmSame, cmUpper, cmLower };
 	virtual std::string CaseMapString(const std::string &s, int caseMapping);
@@ -495,7 +495,7 @@ class Editor : public EditModel, public DocWatcher {
 	bool PositionInSelection(Sci::Position pos);
 	bool PointInSelection(Point pt);
 	bool PointInSelMargin(Point pt) const;
-	Window::Cursor GetMarginCursor(Point pt) const;
+	Window::Cursor GetMarginCursor(Point pt) const noexcept;
 	void TrimAndSetSelection(Sci::Position currentPos_, Sci::Position anchor_);
 	void LineSelection(Sci::Position lineCurrentPos_, Sci::Position lineAnchorPos_, bool wholeLine);
 	void WordSelection(Sci::Position pos);
@@ -522,6 +522,9 @@ class Editor : public EditModel, public DocWatcher {
 	Sci::Position PositionAfterMaxStyling(Sci::Position posMax, bool scrolling) const;
 	void StartIdleStyling(bool truncatedLastStyling);
 	void StyleAreaBounded(PRectangle rcArea, bool scrolling);
+	bool SynchronousStylingToVisible() const noexcept {
+		return (idleStyling == SC_IDLESTYLING_NONE) || (idleStyling == SC_IDLESTYLING_AFTERVISIBLE);
+	}
 	void IdleStyling();
 	virtual void IdleWork();
 	virtual void QueueIdleWork(WorkNeeded::workItems items, Sci::Position upTo=0);
@@ -552,52 +555,54 @@ class Editor : public EditModel, public DocWatcher {
 	bool PositionIsHotspot(Sci::Position position) const;
 	bool PointIsHotspot(Point pt);
 	void SetHotSpotRange(const Point *pt);
-	Range GetHotSpotRange() const override;
+	Range GetHotSpotRange() const noexcept override;
 	void SetHoverIndicatorPosition(Sci::Position position);
 	void SetHoverIndicatorPoint(Point pt);
 
-	int CodePage() const;
+	int CodePage() const noexcept;
 	virtual bool ValidCodePage(int /* codePage */) const { return true; }
 	Sci::Line WrapCount(Sci::Line line);
 	void AddStyledText(const char *buffer, Sci::Position appendLength);
 
 	virtual sptr_t DefWndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) = 0;
-	bool ValidMargin(uptr_t wParam) const;
+	bool ValidMargin(uptr_t wParam) const noexcept;
 	void StyleSetMessage(unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 	sptr_t StyleGetMessage(unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 	void SetSelectionNMessage(unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 
-	static const char *StringFromEOLMode(int eolMode);
+	static const char *StringFromEOLMode(int eolMode) noexcept;
 
 	// Coercion functions for transforming WndProc parameters into pointers
-	static void *PtrFromSPtr(sptr_t lParam) {
+	static void *PtrFromSPtr(sptr_t lParam) noexcept {
 		return reinterpret_cast<void *>(lParam);
 	}
-	static const char *ConstCharPtrFromSPtr(sptr_t lParam) {
+	static const char *ConstCharPtrFromSPtr(sptr_t lParam) noexcept {
 		return static_cast<const char *>(PtrFromSPtr(lParam));
 	}
-	static const unsigned char *ConstUCharPtrFromSPtr(sptr_t lParam) {
+	static const unsigned char *ConstUCharPtrFromSPtr(sptr_t lParam) noexcept {
 		return static_cast<const unsigned char *>(PtrFromSPtr(lParam));
 	}
-	static char *CharPtrFromSPtr(sptr_t lParam) {
+	static char *CharPtrFromSPtr(sptr_t lParam) noexcept {
 		return static_cast<char *>(PtrFromSPtr(lParam));
 	}
-	static unsigned char *UCharPtrFromSPtr(sptr_t lParam) {
+	static unsigned char *UCharPtrFromSPtr(sptr_t lParam) noexcept {
 		return static_cast<unsigned char *>(PtrFromSPtr(lParam));
 	}
-	static void *PtrFromUPtr(uptr_t wParam) {
+	static void *PtrFromUPtr(uptr_t wParam) noexcept {
 		return reinterpret_cast<void *>(wParam);
 	}
-	static const char *ConstCharPtrFromUPtr(uptr_t wParam) {
+	static const char *ConstCharPtrFromUPtr(uptr_t wParam) noexcept {
 		return static_cast<const char *>(PtrFromUPtr(wParam));
 	}
 
-	static sptr_t StringResult(sptr_t lParam, const char *val);
-	static sptr_t BytesResult(sptr_t lParam, const unsigned char *val, size_t len);
+	static sptr_t StringResult(sptr_t lParam, const char *val) noexcept;
+	static sptr_t BytesResult(sptr_t lParam, const unsigned char *val, size_t len) noexcept;
 
 public:
+	~Editor() override;
+
 	// Public so the COM thunks can access it.
-	bool IsUnicodeMode() const;
+	bool IsUnicodeMode() const noexcept;
 	// Public so scintilla_send_message can use it.
 	virtual sptr_t WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam);
 	// Public so scintilla_set_id can use it.
diff --git a/scintilla/src/ElapsedPeriod.h b/scintilla/src/ElapsedPeriod.h
index 1e2c96eb4f..6f8cdabdfa 100644
--- a/scintilla/src/ElapsedPeriod.h
+++ b/scintilla/src/ElapsedPeriod.h
@@ -15,7 +15,7 @@ class ElapsedPeriod {
 	std::chrono::high_resolution_clock::time_point tp;
 public:
 	/// Capture the moment
-	ElapsedPeriod() : tp(std::chrono::high_resolution_clock::now()) {
+	ElapsedPeriod() noexcept : tp(std::chrono::high_resolution_clock::now()) {
 	}
 	/// Return duration as floating point seconds
 	double Duration(bool reset=false) {
diff --git a/scintilla/src/Indicator.cxx b/scintilla/src/Indicator.cxx
index 544bd571d1..24cd408205 100644
--- a/scintilla/src/Indicator.cxx
+++ b/scintilla/src/Indicator.cxx
@@ -25,8 +25,8 @@ using namespace Scintilla;
 
 static PRectangle PixelGridAlign(const PRectangle &rc) {
 	// Move left and right side to nearest pixel to avoid blurry visuals
-	return PRectangle(round(rc.left), floor(rc.top),
-		round(rc.right), floor(rc.bottom));
+	return PRectangle(round(rc.left), std::floor(rc.top),
+		round(rc.right), std::floor(rc.bottom));
 }
 
 void Indicator::Draw(Surface *surface, const PRectangle &rc, const PRectangle &rcLine, const PRectangle &rcCharacter, DrawState drawState, int value) const {
@@ -201,10 +201,10 @@ void Indicator::Draw(Surface *surface, const PRectangle &rc, const PRectangle &r
 		surface->FillRectangle(rcComposition, sacDraw.fore);
 	} else if (sacDraw.style == INDIC_POINT || sacDraw.style == INDIC_POINTCHARACTER) {
 		if (rcCharacter.Width() >= 0.1) {
-			const XYPOSITION pixelHeight = floor(rc.Height() - 1.0f);	// 1 pixel onto next line if multiphase
+			const XYPOSITION pixelHeight = std::floor(rc.Height() - 1.0f);	// 1 pixel onto next line if multiphase
 			const XYPOSITION x = (sacDraw.style == INDIC_POINT) ? (rcCharacter.left) : ((rcCharacter.right + rcCharacter.left) / 2);
 			const XYPOSITION ix = round(x);
-			const XYPOSITION iy = floor(rc.top + 1.0f);
+			const XYPOSITION iy = std::floor(rc.top + 1.0f);
 			Point pts[] = {
 				Point(ix - pixelHeight, iy + pixelHeight),	// Left
 				Point(ix + pixelHeight, iy + pixelHeight),	// Right
diff --git a/scintilla/src/Indicator.h b/scintilla/src/Indicator.h
index 7e9a00ce3a..9e5fda2213 100644
--- a/scintilla/src/Indicator.h
+++ b/scintilla/src/Indicator.h
@@ -13,9 +13,9 @@ namespace Scintilla {
 struct StyleAndColour {
 	int style;
 	ColourDesired fore;
-	StyleAndColour() : style(INDIC_PLAIN), fore(0, 0, 0) {
+	StyleAndColour() noexcept : style(INDIC_PLAIN), fore(0, 0, 0) {
 	}
-	StyleAndColour(int style_, ColourDesired fore_ = ColourDesired(0, 0, 0)) : style(style_), fore(fore_) {
+	StyleAndColour(int style_, ColourDesired fore_ = ColourDesired(0, 0, 0)) noexcept : style(style_), fore(fore_) {
 	}
 	bool operator==(const StyleAndColour &other) const {
 		return (style == other.style) && (fore == other.fore);
@@ -33,9 +33,9 @@ class Indicator {
 	int fillAlpha;
 	int outlineAlpha;
 	int attributes;
-	Indicator() : under(false), fillAlpha(30), outlineAlpha(50), attributes(0) {
+	Indicator() noexcept : under(false), fillAlpha(30), outlineAlpha(50), attributes(0) {
 	}
-	Indicator(int style_, ColourDesired fore_=ColourDesired(0,0,0), bool under_=false, int fillAlpha_=30, int outlineAlpha_=50) :
+	Indicator(int style_, ColourDesired fore_=ColourDesired(0,0,0), bool under_=false, int fillAlpha_=30, int outlineAlpha_=50) noexcept :
 		sacNormal(style_, fore_), sacHover(style_, fore_), under(under_), fillAlpha(fillAlpha_), outlineAlpha(outlineAlpha_), attributes(0) {
 	}
 	void Draw(Surface *surface, const PRectangle &rc, const PRectangle &rcLine, const PRectangle &rcCharacter, DrawState drawState, int value) const;
diff --git a/scintilla/src/KeyMap.h b/scintilla/src/KeyMap.h
index b4299feecb..6f30abf003 100644
--- a/scintilla/src/KeyMap.h
+++ b/scintilla/src/KeyMap.h
@@ -25,7 +25,7 @@ class KeyModifiers {
 public:
 	int key;
 	int modifiers;
-	KeyModifiers(int key_, int modifiers_) : key(key_), modifiers(modifiers_) {
+	KeyModifiers(int key_, int modifiers_) noexcept : key(key_), modifiers(modifiers_) {
 	}
 	bool operator<(const KeyModifiers &other) const {
 		if (key == other.key)
diff --git a/scintilla/src/LineMarker.cxx b/scintilla/src/LineMarker.cxx
index ca542be166..d2c906d083 100644
--- a/scintilla/src/LineMarker.cxx
+++ b/scintilla/src/LineMarker.cxx
@@ -25,41 +25,41 @@
 
 using namespace Scintilla;
 
-LineMarker::~LineMarker() {
-}
-
-LineMarker::LineMarker() {
-	markType = SC_MARK_CIRCLE;
-	fore = ColourDesired(0, 0, 0);
-	back = ColourDesired(0xff, 0xff, 0xff);
-	backSelected = ColourDesired(0xff, 0x00, 0x00);
-	alpha = SC_ALPHA_NOALPHA;
-	customDraw = nullptr;
-}
-
-LineMarker::LineMarker(const LineMarker &) {
+LineMarker::LineMarker(const LineMarker &other) {
 	// Defined to avoid pxpm and image being blindly copied, not as a complete copy constructor.
-	markType = SC_MARK_CIRCLE;
-	fore = ColourDesired(0, 0, 0);
-	back = ColourDesired(0xff, 0xff, 0xff);
-	backSelected = ColourDesired(0xff, 0x00, 0x00);
-	alpha = SC_ALPHA_NOALPHA;
-	pxpm.reset();
-	image.reset();
-	customDraw = nullptr;
+	markType = other.markType;
+	fore = other.fore;
+	back = other.back;
+	backSelected = other.backSelected;
+	alpha = other.alpha;
+	if (other.pxpm)
+		pxpm.reset(new XPM(*other.pxpm));
+	else
+		pxpm = nullptr;
+	if (other.image)
+		image.reset(new RGBAImage(*other.image));
+	else
+		image = nullptr;
+	customDraw = other.customDraw;
 }
 
 LineMarker &LineMarker::operator=(const LineMarker &other) {
 	// Defined to avoid pxpm and image being blindly copied, not as a complete assignment operator.
 	if (this != &other) {
-		markType = SC_MARK_CIRCLE;
-		fore = ColourDesired(0, 0, 0);
-		back = ColourDesired(0xff, 0xff, 0xff);
-		backSelected = ColourDesired(0xff, 0x00, 0x00);
-		alpha = SC_ALPHA_NOALPHA;
-		pxpm.reset();
-		image.reset();
-		customDraw = nullptr;
+		markType = other.markType;
+		fore = other.fore;
+		back = other.back;
+		backSelected = other.backSelected;
+		alpha = other.alpha;
+		if (other.pxpm)
+			pxpm.reset(new XPM(*other.pxpm));
+		else
+			pxpm = nullptr;
+		if (other.image)
+			image.reset(new RGBAImage(*other.image));
+		else
+			image = nullptr;
+		customDraw = other.customDraw;
 	}
 	return *this;
 }
@@ -430,6 +430,16 @@ void LineMarker::Draw(Surface *surface, PRectangle &rcWhole, Font &fontForCharac
 			Point::FromInts(ircWhole.left, centreY + halfHeight),
 		};
 		surface->Polygon(pts, ELEMENTS(pts), fore, back);
+	} else if (markType == SC_MARK_VERTICALBOOKMARK) {
+		const int halfWidth = minDim / 3;
+		Point pts[] = {
+			Point::FromInts(centreX - halfWidth, centreY - dimOn2),
+			Point::FromInts(centreX + halfWidth, centreY - dimOn2),
+			Point::FromInts(centreX + halfWidth, centreY + dimOn2),
+			Point::FromInts(centreX, centreY + dimOn2 - halfWidth),
+			Point::FromInts(centreX - halfWidth, centreY + dimOn2),
+		};
+		surface->Polygon(pts, ELEMENTS(pts), fore, back);
 	} else { // SC_MARK_FULLRECT
 		surface->FillRectangle(rcWhole, back);
 	}
diff --git a/scintilla/src/LineMarker.h b/scintilla/src/LineMarker.h
index 28a63cd3b4..8a15327d2e 100644
--- a/scintilla/src/LineMarker.h
+++ b/scintilla/src/LineMarker.h
@@ -21,22 +21,26 @@ class LineMarker {
 public:
 	enum typeOfFold { undefined, head, body, tail, headWithTail };
 
-	int markType;
-	ColourDesired fore;
-	ColourDesired back;
-	ColourDesired backSelected;
-	int alpha;
+	int markType = SC_MARK_CIRCLE;
+	ColourDesired fore = ColourDesired(0, 0, 0);
+	ColourDesired back = ColourDesired(0xff, 0xff, 0xff);
+	ColourDesired backSelected = ColourDesired(0xff, 0x00, 0x00);
+	int alpha = SC_ALPHA_NOALPHA;
 	std::unique_ptr<XPM> pxpm;
 	std::unique_ptr<RGBAImage> image;
 	/** Some platforms, notably PLAT_CURSES, do not support Scintilla's native
 	 * Draw function for drawing line markers. Allow those platforms to override
 	 * it instead of creating a new method(s) in the Surface class that existing
 	 * platforms must implement as empty. */
-	DrawLineMarkerFn customDraw;
-	LineMarker();
-	LineMarker(const LineMarker &);
-	virtual ~LineMarker();
-	LineMarker &operator=(const LineMarker &other);
+	DrawLineMarkerFn customDraw = nullptr;
+
+	LineMarker() noexcept = default;
+	LineMarker(const LineMarker &other);
+	LineMarker(LineMarker &&) noexcept = default;
+	LineMarker &operator=(const LineMarker& other);
+	LineMarker &operator=(LineMarker&&) noexcept = default;
+	virtual ~LineMarker() = default;
+
 	void SetXPM(const char *textForm);
 	void SetXPM(const char *const *linesForm);
 	void SetRGBAImage(Point sizeRGBAImage, float scale, const unsigned char *pixelsRGBAImage);
diff --git a/scintilla/src/MarginView.cxx b/scintilla/src/MarginView.cxx
index 3662c7eef0..a2fea70a7c 100644
--- a/scintilla/src/MarginView.cxx
+++ b/scintilla/src/MarginView.cxx
@@ -9,7 +9,6 @@
 #include <cstdlib>
 #include <cassert>
 #include <cstring>
-#include <cctype>
 #include <cstdio>
 #include <cmath>
 
@@ -26,6 +25,7 @@
 #include "ILexer.h"
 #include "Scintilla.h"
 
+#include "CharacterCategory.h"
 #include "Position.h"
 #include "IntegerRectangle.h"
 #include "UniqueString.h"
@@ -100,7 +100,7 @@ void DrawWrapMarker(Surface *surface, PRectangle rcPlace,
 		y - 2 * dy);
 }
 
-MarginView::MarginView() {
+MarginView::MarginView() noexcept {
 	wrapMarkerPaddingRight = 3;
 	customDrawWrapMarker = nullptr;
 }
diff --git a/scintilla/src/MarginView.h b/scintilla/src/MarginView.h
index 1d5d46caca..4468afa1be 100644
--- a/scintilla/src/MarginView.h
+++ b/scintilla/src/MarginView.h
@@ -32,7 +32,7 @@ class MarginView {
 	 * existing platforms must implement as empty. */
 	DrawWrapMarkerFn customDrawWrapMarker;
 
-	MarginView();
+	MarginView() noexcept;
 
 	void DropGraphics(bool freeObjects);
 	void AllocateGraphics(const ViewStyle &vsDraw);
diff --git a/scintilla/src/PerLine.h b/scintilla/src/PerLine.h
index bf0968f28a..94dc17a204 100644
--- a/scintilla/src/PerLine.h
+++ b/scintilla/src/PerLine.h
@@ -17,7 +17,7 @@ namespace Scintilla {
 struct MarkerHandleNumber {
 	int handle;
 	int number;
-	MarkerHandleNumber(int handle_, int number_) : handle(handle_), number(number_) {}
+	MarkerHandleNumber(int handle_, int number_) noexcept : handle(handle_), number(number_) {}
 };
 
 /**
diff --git a/scintilla/src/PositionCache.cxx b/scintilla/src/PositionCache.cxx
index 3b3014ab58..b1b55bd500 100644
--- a/scintilla/src/PositionCache.cxx
+++ b/scintilla/src/PositionCache.cxx
@@ -24,6 +24,7 @@
 #include "ILexer.h"
 #include "Scintilla.h"
 
+#include "CharacterCategory.h"
 #include "Position.h"
 #include "UniqueString.h"
 #include "SplitVector.h"
@@ -82,7 +83,7 @@ void LineLayout::Resize(int maxLineLength_) {
 	}
 }
 
-void LineLayout::Free() {
+void LineLayout::Free() noexcept {
 	chars.reset();
 	styles.reset();
 	positions.reset();
@@ -283,7 +284,7 @@ void LineLayoutCache::AllocateForLevel(Sci::Line linesOnScreen, Sci::Line linesI
 	PLATFORM_ASSERT(cache.size() == lengthForLevel);
 }
 
-void LineLayoutCache::Deallocate() {
+void LineLayoutCache::Deallocate() noexcept {
 	PLATFORM_ASSERT(useCount == 0);
 	cache.clear();
 }
@@ -301,7 +302,7 @@ void LineLayoutCache::Invalidate(LineLayout::validLevel validity_) {
 	}
 }
 
-void LineLayoutCache::SetLevel(int level_) {
+void LineLayoutCache::SetLevel(int level_) noexcept {
 	allInvalidated = false;
 	if ((level_ != -1) && (level != level_)) {
 		level = level_;
@@ -357,7 +358,7 @@ LineLayout *LineLayoutCache::Retrieve(Sci::Line lineNumber, Sci::Line lineCaret,
 	return ret;
 }
 
-void LineLayoutCache::Dispose(LineLayout *ll) {
+void LineLayoutCache::Dispose(LineLayout *ll) noexcept {
 	allInvalidated = false;
 	if (ll) {
 		if (!ll->inCache) {
@@ -380,7 +381,7 @@ static unsigned int KeyFromString(const char *charBytes, size_t len) {
 	return k;
 }
 
-SpecialRepresentations::SpecialRepresentations() {
+SpecialRepresentations::SpecialRepresentations() noexcept {
 	const short none = 0;
 	std::fill(startByteHasReprs, std::end(startByteHasReprs), none);
 }
@@ -556,11 +557,11 @@ TextSegment BreakFinder::Next() {
 	}
 }
 
-bool BreakFinder::More() const {
+bool BreakFinder::More() const noexcept {
 	return (subBreak >= 0) || (nextBreak < lineRange.end);
 }
 
-PositionCacheEntry::PositionCacheEntry() :
+PositionCacheEntry::PositionCacheEntry() noexcept :
 	styleNumber(0), len(0), clock(0), positions(nullptr) {
 }
 
@@ -593,7 +594,7 @@ PositionCacheEntry::~PositionCacheEntry() {
 	Clear();
 }
 
-void PositionCacheEntry::Clear() {
+void PositionCacheEntry::Clear() noexcept {
 	positions.reset();
 	styleNumber = 0;
 	len = 0;
@@ -613,7 +614,7 @@ bool PositionCacheEntry::Retrieve(unsigned int styleNumber_, const char *s_,
 	}
 }
 
-unsigned int PositionCacheEntry::Hash(unsigned int styleNumber_, const char *s, unsigned int len_) {
+unsigned int PositionCacheEntry::Hash(unsigned int styleNumber_, const char *s, unsigned int len_) noexcept {
 	unsigned int ret = s[0] << 7;
 	for (unsigned int i=0; i<len_; i++) {
 		ret *= 1000003;
@@ -626,11 +627,11 @@ unsigned int PositionCacheEntry::Hash(unsigned int styleNumber_, const char *s,
 	return ret;
 }
 
-bool PositionCacheEntry::NewerThan(const PositionCacheEntry &other) const {
+bool PositionCacheEntry::NewerThan(const PositionCacheEntry &other) const noexcept {
 	return clock > other.clock;
 }
 
-void PositionCacheEntry::ResetClock() {
+void PositionCacheEntry::ResetClock() noexcept {
 	if (clock > 0) {
 		clock = 1;
 	}
@@ -646,7 +647,7 @@ PositionCache::~PositionCache() {
 	Clear();
 }
 
-void PositionCache::Clear() {
+void PositionCache::Clear() noexcept {
 	if (!allClear) {
 		for (PositionCacheEntry &pce : pces) {
 			pce.Clear();
diff --git a/scintilla/src/PositionCache.h b/scintilla/src/PositionCache.h
index c3973eba9f..6899ba99f7 100644
--- a/scintilla/src/PositionCache.h
+++ b/scintilla/src/PositionCache.h
@@ -86,7 +86,7 @@ class LineLayout {
 	void operator=(LineLayout &&) = delete;
 	virtual ~LineLayout();
 	void Resize(int maxLineLength_);
-	void Free();
+	void Free() noexcept;
 	void Invalidate(validLevel validity_);
 	int LineStart(int line) const;
 	enum class Scope { visibleOnly, includeEnd };
@@ -121,7 +121,7 @@ class LineLayoutCache {
 	void operator=(const LineLayoutCache &) = delete;
 	void operator=(LineLayoutCache &&) = delete;
 	virtual ~LineLayoutCache();
-	void Deallocate();
+	void Deallocate() noexcept;
 	enum {
 		llcNone=SC_CACHE_NONE,
 		llcCaret=SC_CACHE_CARET,
@@ -129,11 +129,11 @@ class LineLayoutCache {
 		llcDocument=SC_CACHE_DOCUMENT
 	};
 	void Invalidate(LineLayout::validLevel validity_);
-	void SetLevel(int level_);
-	int GetLevel() const { return level; }
+	void SetLevel(int level_) noexcept;
+	int GetLevel() const noexcept { return level; }
 	LineLayout *Retrieve(Sci::Line lineNumber, Sci::Line lineCaret, int maxChars, int styleClock_,
 		Sci::Line linesOnScreen, Sci::Line linesInDoc);
-	void Dispose(LineLayout *ll);
+	void Dispose(LineLayout *ll) noexcept;
 };
 
 class PositionCacheEntry {
@@ -142,7 +142,7 @@ class PositionCacheEntry {
 	unsigned int clock:16;
 	std::unique_ptr<XYPOSITION []> positions;
 public:
-	PositionCacheEntry();
+	PositionCacheEntry() noexcept;
 	// Copy constructor not currently used, but needed for being element in std::vector.
 	PositionCacheEntry(const PositionCacheEntry &);
 	// PositionCacheEntry objects should not be moved but MSVC 2015 requires this.
@@ -151,11 +151,11 @@ class PositionCacheEntry {
 	void operator=(PositionCacheEntry &&) = delete;
 	~PositionCacheEntry();
 	void Set(unsigned int styleNumber_, const char *s_, unsigned int len_, const XYPOSITION *positions_, unsigned int clock_);
-	void Clear();
+	void Clear() noexcept;
 	bool Retrieve(unsigned int styleNumber_, const char *s_, unsigned int len_, XYPOSITION *positions_) const;
-	static unsigned int Hash(unsigned int styleNumber_, const char *s, unsigned int len_);
-	bool NewerThan(const PositionCacheEntry &other) const;
-	void ResetClock();
+	static unsigned int Hash(unsigned int styleNumber_, const char *s, unsigned int len_) noexcept;
+	bool NewerThan(const PositionCacheEntry &other) const noexcept;
+	void ResetClock() noexcept;
 };
 
 class Representation {
@@ -171,7 +171,7 @@ class SpecialRepresentations {
 	MapRepresentation mapReprs;
 	short startByteHasReprs[0x100];
 public:
-	SpecialRepresentations();
+	SpecialRepresentations() noexcept;
 	void SetRepresentation(const char *charBytes, const char *value);
 	void ClearRepresentation(const char *charBytes);
 	const Representation *RepresentationFromCharacter(const char *charBytes, size_t len) const;
@@ -220,7 +220,7 @@ class BreakFinder {
 	void operator=(BreakFinder &&) = delete;
 	~BreakFinder();
 	TextSegment Next();
-	bool More() const;
+	bool More() const noexcept;
 };
 
 class PositionCache {
@@ -235,9 +235,9 @@ class PositionCache {
 	void operator=(const PositionCache &) = delete;
 	void operator=(PositionCache &&) = delete;
 	~PositionCache();
-	void Clear();
+	void Clear() noexcept;
 	void SetSize(size_t size_);
-	size_t GetSize() const { return pces.size(); }
+	size_t GetSize() const noexcept { return pces.size(); }
 	void MeasureWidths(Surface *surface, const ViewStyle &vstyle, unsigned int styleNumber,
 		const char *s, unsigned int len, XYPOSITION *positions, const Document *pdoc);
 };
diff --git a/scintilla/src/RESearch.h b/scintilla/src/RESearch.h
index 285c9dc622..213055daca 100644
--- a/scintilla/src/RESearch.h
+++ b/scintilla/src/RESearch.h
@@ -11,14 +11,6 @@
 
 namespace Scintilla {
 
-/*
- * The following defines are not meant to be changeable.
- * They are for readability only.
- */
-#define MAXCHR	256
-#define CHRBIT	8
-#define BITBLK	MAXCHR/CHRBIT
-
 class CharacterIndexer {
 public:
 	virtual char CharAt(Sci::Position index) const=0;
@@ -38,7 +30,6 @@ class RESearch {
 	int Execute(const CharacterIndexer &ci, Sci::Position lp, Sci::Position endp);
 
 	enum { MAXTAG=10 };
-	enum { MAXNFA=4096 };
 	enum { NOTFOUND=-1 };
 
 	Sci::Position bopat[MAXTAG];
@@ -46,6 +37,14 @@ class RESearch {
 	std::string pat[MAXTAG];
 
 private:
+
+	enum { MAXNFA = 4096 };
+	// The following enums are not meant to be changeable.
+	// They are for readability only.
+	enum { MAXCHR = 256 };
+	enum { CHRBIT = 8 };
+	enum { BITBLK = MAXCHR / CHRBIT };
+
 	void ChSet(unsigned char c);
 	void ChSetWithCase(unsigned char c, bool caseSensitive);
 	int GetBackslashExpression(const char *pattern, int &incr);
diff --git a/scintilla/src/ScintillaBase.cxx b/scintilla/src/ScintillaBase.cxx
index c327206d8b..0c00309b7b 100644
--- a/scintilla/src/ScintillaBase.cxx
+++ b/scintilla/src/ScintillaBase.cxx
@@ -28,6 +28,7 @@
 #endif
 
 #include "PropSetSimple.h"
+#include "CharacterCategory.h"
 
 #ifdef SCI_LEXER
 #include "LexerModule.h"
@@ -275,9 +276,7 @@ void ScintillaBase::AutoCompleteStart(Sci::Position lenEntered, const char *list
 		pt = PointMainCaret();
 	}
 	if (wMargin.Created()) {
-		const Point ptOrigin = GetVisibleOriginInMain();
-		pt.x += ptOrigin.x;
-		pt.y += ptOrigin.y;
+		pt = pt + GetVisibleOriginInMain();
 	}
 	PRectangle rcac;
 	rcac.left = pt.x - ac.lb->CaretFromEdge();
@@ -462,9 +461,7 @@ void ScintillaBase::CallTipShow(Point pt, const char *defn) {
 		ct.SetForeBack(vs.styles[STYLE_CALLTIP].fore, vs.styles[STYLE_CALLTIP].back);
 	}
 	if (wMargin.Created()) {
-		const Point ptOrigin = GetVisibleOriginInMain();
-		pt.x += ptOrigin.x;
-		pt.y += ptOrigin.y;
+		pt = pt + GetVisibleOriginInMain();
 	}
 	PRectangle rc = ct.CallTipStart(sel.MainCaret(), pt,
 		vs.lineHeight,
diff --git a/scintilla/src/ScintillaBase.h b/scintilla/src/ScintillaBase.h
index e886f22e2e..39fb9d411c 100644
--- a/scintilla/src/ScintillaBase.h
+++ b/scintilla/src/ScintillaBase.h
@@ -57,7 +57,7 @@ class ScintillaBase : public Editor, IListBoxDelegate {
 	ScintillaBase(ScintillaBase &&) = delete;
 	ScintillaBase &operator=(const ScintillaBase &) = delete;
 	ScintillaBase &operator=(ScintillaBase &&) = delete;
-	~ScintillaBase() override;
+	// ~ScintillaBase() in public section
 	void Initialise() override {}
 	void Finalise() override;
 
@@ -94,6 +94,8 @@ class ScintillaBase : public Editor, IListBoxDelegate {
 	void NotifyLexerChanged(Document *doc, void *userData) override;
 
 public:
+	~ScintillaBase() override;
+
 	// Public so scintilla_send_message can use it
 	sptr_t WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) override;
 };
diff --git a/scintilla/src/Selection.cxx b/scintilla/src/Selection.cxx
index c8c567fcb5..db13a55ad0 100644
--- a/scintilla/src/Selection.cxx
+++ b/scintilla/src/Selection.cxx
@@ -176,7 +176,7 @@ void SelectionRange::MinimizeVirtualSpace() {
 	}
 }
 
-Selection::Selection() : mainRange(0), moveExtends(false), tentativeMain(false), selType(selStream) {
+Selection::Selection() noexcept : mainRange(0), moveExtends(false), tentativeMain(false), selType(selStream) {
 	AddSelection(SelectionRange(SelectionPosition(0)));
 }
 
diff --git a/scintilla/src/Selection.h b/scintilla/src/Selection.h
index 8f21669611..82fc4aa487 100644
--- a/scintilla/src/Selection.h
+++ b/scintilla/src/Selection.h
@@ -14,7 +14,7 @@ class SelectionPosition {
 	Sci::Position position;
 	Sci::Position virtualSpace;
 public:
-	explicit SelectionPosition(Sci::Position position_=INVALID_POSITION, Sci::Position virtualSpace_=0) : position(position_), virtualSpace(virtualSpace_) {
+	explicit SelectionPosition(Sci::Position position_=INVALID_POSITION, Sci::Position virtualSpace_=0) noexcept : position(position_), virtualSpace(virtualSpace_) {
 		PLATFORM_ASSERT(virtualSpace < 800000);
 		if (virtualSpace < 0)
 			virtualSpace = 0;
@@ -84,15 +84,15 @@ struct SelectionRange {
 	SelectionPosition caret;
 	SelectionPosition anchor;
 
-	SelectionRange() : caret(), anchor() {
+	SelectionRange() noexcept : caret(), anchor() {
 	}
-	explicit SelectionRange(SelectionPosition single) : caret(single), anchor(single) {
+	explicit SelectionRange(SelectionPosition single) noexcept : caret(single), anchor(single) {
 	}
-	explicit SelectionRange(Sci::Position single) : caret(single), anchor(single) {
+	explicit SelectionRange(Sci::Position single) noexcept : caret(single), anchor(single) {
 	}
-	SelectionRange(SelectionPosition caret_, SelectionPosition anchor_) : caret(caret_), anchor(anchor_) {
+	SelectionRange(SelectionPosition caret_, SelectionPosition anchor_) noexcept : caret(caret_), anchor(anchor_) {
 	}
-	SelectionRange(Sci::Position caret_, Sci::Position anchor_) : caret(caret_), anchor(anchor_) {
+	SelectionRange(Sci::Position caret_, Sci::Position anchor_) noexcept : caret(caret_), anchor(anchor_) {
 	}
 	bool Empty() const {
 		return anchor == caret;
@@ -141,7 +141,7 @@ class Selection {
 	enum selTypes { noSel, selStream, selRectangle, selLines, selThin };
 	selTypes selType;
 
-	Selection();
+	Selection() noexcept;
 	~Selection();
 	bool IsRectangular() const;
 	Sci::Position MainCaret() const;
diff --git a/scintilla/src/Style.cxx b/scintilla/src/Style.cxx
index 2cb82616b7..b5f8ca091f 100644
--- a/scintilla/src/Style.cxx
+++ b/scintilla/src/Style.cxx
@@ -16,27 +16,27 @@
 
 using namespace Scintilla;
 
-FontAlias::FontAlias() {
+FontAlias::FontAlias() noexcept {
 }
 
-FontAlias::FontAlias(const FontAlias &other) : Font() {
+FontAlias::FontAlias(const FontAlias &other) noexcept : Font() {
 	SetID(other.fid);
 }
 
 FontAlias::~FontAlias() {
-	SetID(0);
+	SetID(FontID{});
 	// ~Font will not release the actual font resource since it is now 0
 }
 
-void FontAlias::MakeAlias(const Font &fontOrigin) {
+void FontAlias::MakeAlias(const Font &fontOrigin) noexcept {
 	SetID(fontOrigin.GetID());
 }
 
-void FontAlias::ClearFont() {
-	SetID(0);
+void FontAlias::ClearFont() noexcept {
+	SetID(FontID{});
 }
 
-bool FontSpecification::operator==(const FontSpecification &other) const {
+bool FontSpecification::operator==(const FontSpecification &other) const noexcept {
 	return fontName == other.fontName &&
 	       weight == other.weight &&
 	       italic == other.italic &&
@@ -45,7 +45,7 @@ bool FontSpecification::operator==(const FontSpecification &other) const {
 	       extraFontFlag == other.extraFontFlag;
 }
 
-bool FontSpecification::operator<(const FontSpecification &other) const {
+bool FontSpecification::operator<(const FontSpecification &other) const noexcept {
 	if (fontName != other.fontName)
 		return fontName < other.fontName;
 	if (weight != other.weight)
@@ -61,11 +61,11 @@ bool FontSpecification::operator<(const FontSpecification &other) const {
 	return false;
 }
 
-FontMeasurements::FontMeasurements() {
+FontMeasurements::FontMeasurements() noexcept {
 	ClearMeasurements();
 }
 
-void FontMeasurements::ClearMeasurements() {
+void FontMeasurements::ClearMeasurements() noexcept {
 	ascent = 1;
 	descent = 1;
 	capitalHeight = 1;
diff --git a/scintilla/src/Style.h b/scintilla/src/Style.h
index 7a497b36ba..1f7f02fe63 100644
--- a/scintilla/src/Style.h
+++ b/scintilla/src/Style.h
@@ -17,7 +17,7 @@ struct FontSpecification {
 	int size;
 	int characterSet;
 	int extraFontFlag;
-	FontSpecification() :
+	FontSpecification() noexcept :
 		fontName(nullptr),
 		weight(SC_WEIGHT_NORMAL),
 		italic(false),
@@ -25,22 +25,22 @@ struct FontSpecification {
 		characterSet(0),
 		extraFontFlag(0) {
 	}
-	bool operator==(const FontSpecification &other) const;
-	bool operator<(const FontSpecification &other) const;
+	bool operator==(const FontSpecification &other) const noexcept;
+	bool operator<(const FontSpecification &other) const noexcept;
 };
 
 // Just like Font but only has a copy of the FontID so should not delete it
 class FontAlias : public Font {
 public:
-	FontAlias();
+	FontAlias() noexcept;
 	// FontAlias objects can not be assigned except for initialization
-	FontAlias(const FontAlias &);
+	FontAlias(const FontAlias &) noexcept;
 	FontAlias(FontAlias &&)  = delete;
 	FontAlias &operator=(const FontAlias &) = delete;
 	FontAlias &operator=(FontAlias &&) = delete;
 	~FontAlias() override;
-	void MakeAlias(const Font &fontOrigin);
-	void ClearFont();
+	void MakeAlias(const Font &fontOrigin) noexcept;
+	void ClearFont() noexcept;
 };
 
 struct FontMeasurements {
@@ -50,8 +50,8 @@ struct FontMeasurements {
 	XYPOSITION aveCharWidth;
 	XYPOSITION spaceWidth;
 	int sizeZoomed;
-	FontMeasurements();
-	void ClearMeasurements();
+	FontMeasurements() noexcept;
+	void ClearMeasurements() noexcept;
 };
 
 /**
@@ -84,7 +84,7 @@ class Style : public FontSpecification, public FontMeasurements {
 	           bool visible_, bool changeable_, bool hotspot_);
 	void ClearTo(const Style &source);
 	void Copy(Font &font_, const FontMeasurements &fm_);
-	bool IsProtected() const { return !(changeable && visible);}
+	bool IsProtected() const noexcept { return !(changeable && visible);}
 };
 
 }
diff --git a/scintilla/src/UniConversion.cxx b/scintilla/src/UniConversion.cxx
index 6cd6a8ba91..5b75ca63cd 100644
--- a/scintilla/src/UniConversion.cxx
+++ b/scintilla/src/UniConversion.cxx
@@ -16,7 +16,7 @@ using namespace Scintilla;
 
 namespace Scintilla {
 
-size_t UTF8Length(const wchar_t *uptr, size_t tlen) {
+size_t UTF8Length(const wchar_t *uptr, size_t tlen) noexcept {
 	size_t len = 0;
 	for (size_t i = 0; i < tlen && uptr[i];) {
 		const unsigned int uch = uptr[i];
@@ -65,7 +65,7 @@ void UTF8FromUTF16(const wchar_t *uptr, size_t tlen, char *putf, size_t len) {
 		putf[k] = '\0';
 }
 
-void UTF8FromUTF32Character(int uch, char *putf) {
+void UTF8FromUTF32Character(int uch, char *putf) noexcept {
 	size_t k = 0;
 	if (uch < 0x80) {
 		putf[k++] = static_cast<char>(uch);
@@ -85,7 +85,7 @@ void UTF8FromUTF32Character(int uch, char *putf) {
 	putf[k] = '\0';
 }
 
-size_t UTF16Length(const char *s, size_t len) {
+size_t UTF16Length(const char *s, size_t len) noexcept {
 	size_t ulen = 0;
 	for (size_t i = 0; i < len;) {
 		const unsigned char ch = s[i];
@@ -162,6 +162,17 @@ size_t UTF16FromUTF8(const char *s, size_t len, wchar_t *tbuf, size_t tlen) {
 	return ui;
 }
 
+size_t UTF32Length(const char *s, size_t len) noexcept {
+	size_t ulen = 0;
+	for (size_t i = 0; i < len;) {
+		const unsigned char ch = s[i];
+		const unsigned int byteCount = UTF8BytesOfLead[ch];
+		i += byteCount;
+		ulen++;
+	}
+	return ulen;
+}
+
 size_t UTF32FromUTF8(const char *s, size_t len, unsigned int *tbuf, size_t tlen) {
 	size_t ui = 0;
 	for (size_t i = 0; i < len;) {
@@ -215,6 +226,20 @@ size_t UTF32FromUTF8(const char *s, size_t len, unsigned int *tbuf, size_t tlen)
 	return ui;
 }
 
+std::wstring WStringFromUTF8(const char *s, size_t len) {
+#ifdef _WIN32
+		const size_t len16 = UTF16Length(s, len);
+		std::wstring ws(len16, 0);
+		UTF16FromUTF8(s, len, &ws[0], len16);
+		return ws;
+#else
+		const size_t len32 = UTF32Length(s, len);
+		std::wstring ws(len32, 0);
+		UTF32FromUTF8(s, len, reinterpret_cast<unsigned int *>(&ws[0]), len32);
+		return ws;
+#endif
+}
+
 unsigned int UTF16FromUTF32Character(unsigned int val, wchar_t *tbuf) noexcept {
 	if (val < SUPPLEMENTAL_PLANE_FIRST) {
 		tbuf[0] = static_cast<wchar_t>(val);
diff --git a/scintilla/src/UniConversion.h b/scintilla/src/UniConversion.h
index 4bb8875d0e..e8e98df5f2 100644
--- a/scintilla/src/UniConversion.h
+++ b/scintilla/src/UniConversion.h
@@ -14,12 +14,16 @@ const int UTF8MaxBytes = 4;
 
 const int unicodeReplacementChar = 0xFFFD;
 
-size_t UTF8Length(const wchar_t *uptr, size_t tlen);
+size_t UTF8Length(const wchar_t *uptr, size_t tlen) noexcept;
 void UTF8FromUTF16(const wchar_t *uptr, size_t tlen, char *putf, size_t len);
-void UTF8FromUTF32Character(int uch, char *putf);
-size_t UTF16Length(const char *s, size_t len);
+void UTF8FromUTF32Character(int uch, char *putf) noexcept;
+size_t UTF16Length(const char *s, size_t len) noexcept;
 size_t UTF16FromUTF8(const char *s, size_t len, wchar_t *tbuf, size_t tlen);
+size_t UTF32Length(const char *s, size_t len) noexcept;
 size_t UTF32FromUTF8(const char *s, size_t len, unsigned int *tbuf, size_t tlen);
+// WStringFromUTF8 does the right thing when wchar_t is 2 or 4 bytes so
+// works on both Windows and Unix.
+std::wstring WStringFromUTF8(const char *s, size_t len);
 unsigned int UTF16FromUTF32Character(unsigned int val, wchar_t *tbuf) noexcept;
 bool UTF8IsValid(const char *s, size_t len) noexcept;
 std::string FixInvalidUTF8(const std::string &text);
diff --git a/scintilla/src/UniqueString.cxx b/scintilla/src/UniqueString.cxx
new file mode 100644
index 0000000000..aadc2ae7e6
--- /dev/null
+++ b/scintilla/src/UniqueString.cxx
@@ -0,0 +1,55 @@
+// Scintilla source code edit control
+/** @file UniqueString.cxx
+ ** Define an allocator for UniqueString.
+ **/
+// Copyright 2017 by Neil Hodgson <neilh@scintilla.org>
+// The License.txt file describes the conditions under which this software may be distributed.
+
+#include <cstring>
+#include <vector>
+#include <algorithm>
+#include <memory>
+
+#include "UniqueString.h"
+
+namespace Scintilla {
+
+/// Equivalent to strdup but produces a std::unique_ptr<const char[]> allocation to go
+/// into collections.
+UniqueString UniqueStringCopy(const char *text) {
+	if (!text) {
+		return UniqueString();
+	}
+	const size_t len = strlen(text);
+	std::unique_ptr<char[]> upcNew(new char[len + 1]);
+	memcpy(&upcNew[0], text, len + 1);
+	return UniqueString(upcNew.release());
+}
+
+// A set of strings that always returns the same pointer for each string.
+
+UniqueStringSet::UniqueStringSet() noexcept = default;
+
+UniqueStringSet::~UniqueStringSet() {
+	strings.clear();
+}
+
+void UniqueStringSet::Clear() noexcept {
+	strings.clear();
+}
+
+const char *UniqueStringSet::Save(const char *text) {
+	if (!text)
+		return nullptr;
+
+	for (const UniqueString &us : strings) {
+		if (text == us.get()) {
+			return us.get();
+		}
+	}
+
+	strings.push_back(UniqueStringCopy(text));
+	return strings.back().get();
+}
+
+}
diff --git a/scintilla/src/UniqueString.h b/scintilla/src/UniqueString.h
index 18c31283e6..f7f7ebbdcb 100644
--- a/scintilla/src/UniqueString.h
+++ b/scintilla/src/UniqueString.h
@@ -2,6 +2,8 @@
 /** @file UniqueString.h
  ** Define UniqueString, a unique_ptr based string type for storage in containers
  ** and an allocator for UniqueString.
+ ** Define UniqueStringSet which holds a set of strings, used to avoid holding many copies
+ ** of font names.
  **/
 // Copyright 2017 by Neil Hodgson <neilh@scintilla.org>
 // The License.txt file describes the conditions under which this software may be distributed.
@@ -11,19 +13,33 @@
 
 namespace Scintilla {
 
+constexpr bool IsNullOrEmpty(const char *text) noexcept {
+	return text == nullptr || *text == '\0';
+}
+
 using UniqueString = std::unique_ptr<const char[]>;
 
 /// Equivalent to strdup but produces a std::unique_ptr<const char[]> allocation to go
 /// into collections.
-inline UniqueString UniqueStringCopy(const char *text) {
-	if (!text) {
-		return UniqueString();
-	}
-	const size_t len = strlen(text);
-	char *sNew = new char[len + 1];
-	std::copy(text, text + len + 1, sNew);
-	return UniqueString(sNew);
-}
+UniqueString UniqueStringCopy(const char *text);
+
+// A set of strings that always returns the same pointer for each string.
+
+class UniqueStringSet {
+private:
+	std::vector<UniqueString> strings;
+public:
+	UniqueStringSet() noexcept;
+	// UniqueStringSet objects can not be copied.
+	UniqueStringSet(const UniqueStringSet &) = delete;
+	UniqueStringSet &operator=(const UniqueStringSet &) = delete;
+	// UniqueStringSet objects can be moved.
+	UniqueStringSet(UniqueStringSet &&) = default;
+	UniqueStringSet &operator=(UniqueStringSet &&) = default;
+	~UniqueStringSet();
+	void Clear() noexcept;
+	const char *Save(const char *text);
+};
 
 }
 
diff --git a/scintilla/src/ViewStyle.cxx b/scintilla/src/ViewStyle.cxx
index 0168556156..a4535abca0 100644
--- a/scintilla/src/ViewStyle.cxx
+++ b/scintilla/src/ViewStyle.cxx
@@ -28,38 +28,11 @@
 
 using namespace Scintilla;
 
-MarginStyle::MarginStyle(int style_, int width_, int mask_) :
+MarginStyle::MarginStyle(int style_, int width_, int mask_) noexcept :
 	style(style_), width(width_), mask(mask_), sensitive(false), cursor(SC_CURSORREVERSEARROW) {
 }
 
-// A list of the fontnames - avoids wasting space in each style
-FontNames::FontNames() {
-}
-
-FontNames::~FontNames() {
-	Clear();
-}
-
-void FontNames::Clear() {
-	names.clear();
-}
-
-const char *FontNames::Save(const char *name) {
-	if (!name)
-		return nullptr;
-
-	for (const UniqueString &nm : names) {
-		if (strcmp(nm.get(), name) == 0) {
-			return nm.get();
-		}
-	}
-
-	names.push_back(UniqueStringCopy(name));
-	return names.back().get();
-}
-
-FontRealised::FontRealised() {
-}
+FontRealised::FontRealised() noexcept = default;
 
 FontRealised::~FontRealised() {
 	font.Release();
@@ -373,7 +346,7 @@ void ViewStyle::Refresh(Surface &surface, int tabInChars) {
 	textStart = marginInside ? fixedColumnWidth : leftMarginWidth;
 }
 
-void ViewStyle::ReleaseAllExtendedStyles() {
+void ViewStyle::ReleaseAllExtendedStyles() noexcept {
 	nextExtendedStyle = 256;
 }
 
@@ -419,11 +392,11 @@ void ViewStyle::SetStyleFontName(int styleIndex, const char *name) {
 	styles[styleIndex].fontName = fontNames.Save(name);
 }
 
-bool ViewStyle::ProtectionActive() const {
+bool ViewStyle::ProtectionActive() const noexcept {
 	return someStylesProtected;
 }
 
-int ViewStyle::ExternalMarginWidth() const {
+int ViewStyle::ExternalMarginWidth() const noexcept {
 	return marginInside ? 0 : fixedColumnWidth;
 }
 
@@ -438,7 +411,7 @@ int ViewStyle::MarginFromLocation(Point pt) const {
 	return margin;
 }
 
-bool ViewStyle::ValidStyle(size_t styleIndex) const {
+bool ViewStyle::ValidStyle(size_t styleIndex) const noexcept {
 	return styleIndex < styles.size();
 }
 
@@ -458,11 +431,11 @@ void ViewStyle::CalcLargestMarkerHeight() {
 	}
 }
 
-int ViewStyle::GetFrameWidth() const {
+int ViewStyle::GetFrameWidth() const noexcept {
 	return Sci::clamp(caretLineFrame, 1, lineHeight / 3);
 }
 
-bool ViewStyle::IsLineFrameOpaque(bool caretActive, bool lineContainsCaret) const {
+bool ViewStyle::IsLineFrameOpaque(bool caretActive, bool lineContainsCaret) const noexcept {
 	return caretLineFrame && (caretActive || alwaysShowCaretLineBackground) && showCaretLineBackground &&
 		(caretLineAlpha == SC_ALPHA_NOALPHA) && lineContainsCaret;
 }
@@ -504,16 +477,16 @@ ColourOptional ViewStyle::Background(int marksOfLine, bool caretActive, bool lin
 	return background;
 }
 
-bool ViewStyle::SelectionBackgroundDrawn() const {
+bool ViewStyle::SelectionBackgroundDrawn() const noexcept {
 	return selColours.back.isSet &&
 		((selAlpha == SC_ALPHA_NOALPHA) || (selAdditionalAlpha == SC_ALPHA_NOALPHA));
 }
 
-bool ViewStyle::WhitespaceBackgroundDrawn() const {
+bool ViewStyle::WhitespaceBackgroundDrawn() const noexcept {
 	return (viewWhitespace != wsInvisible) && (whitespaceColours.back.isSet);
 }
 
-bool ViewStyle::WhiteSpaceVisible(bool inIndent) const {
+bool ViewStyle::WhiteSpaceVisible(bool inIndent) const noexcept {
 	return (!inIndent && viewWhitespace == wsVisibleAfterIndent) ||
 		(inIndent && viewWhitespace == wsVisibleOnlyInIndent) ||
 		viewWhitespace == wsVisibleAlways;
@@ -526,7 +499,7 @@ ColourDesired ViewStyle::WrapColour() const {
 		return styles[STYLE_DEFAULT].fore;
 }
 
-bool ViewStyle::SetWrapState(int wrapState_) {
+bool ViewStyle::SetWrapState(int wrapState_) noexcept {
 	WrapMode wrapStateWanted;
 	switch (wrapState_) {
 	case SC_WRAP_WORD:
@@ -547,30 +520,43 @@ bool ViewStyle::SetWrapState(int wrapState_) {
 	return changed;
 }
 
-bool ViewStyle::SetWrapVisualFlags(int wrapVisualFlags_) {
+bool ViewStyle::SetWrapVisualFlags(int wrapVisualFlags_) noexcept {
 	const bool changed = wrapVisualFlags != wrapVisualFlags_;
 	wrapVisualFlags = wrapVisualFlags_;
 	return changed;
 }
 
-bool ViewStyle::SetWrapVisualFlagsLocation(int wrapVisualFlagsLocation_) {
+bool ViewStyle::SetWrapVisualFlagsLocation(int wrapVisualFlagsLocation_) noexcept {
 	const bool changed = wrapVisualFlagsLocation != wrapVisualFlagsLocation_;
 	wrapVisualFlagsLocation = wrapVisualFlagsLocation_;
 	return changed;
 }
 
-bool ViewStyle::SetWrapVisualStartIndent(int wrapVisualStartIndent_) {
+bool ViewStyle::SetWrapVisualStartIndent(int wrapVisualStartIndent_) noexcept {
 	const bool changed = wrapVisualStartIndent != wrapVisualStartIndent_;
 	wrapVisualStartIndent = wrapVisualStartIndent_;
 	return changed;
 }
 
-bool ViewStyle::SetWrapIndentMode(int wrapIndentMode_) {
+bool ViewStyle::SetWrapIndentMode(int wrapIndentMode_) noexcept {
 	const bool changed = wrapIndentMode != wrapIndentMode_;
 	wrapIndentMode = wrapIndentMode_;
 	return changed;
 }
 
+bool ViewStyle::IsBlockCaretStyle() const noexcept {
+	return (caretStyle == CARETSTYLE_BLOCK) || (caretStyle & CARETSTYLE_OVERSTRIKE_BLOCK) != 0;
+}
+
+ViewStyle::CaretShape ViewStyle::CaretShapeForMode(bool inOverstrike) const noexcept {
+	if (inOverstrike) {
+		return (caretStyle & CARETSTYLE_OVERSTRIKE_BLOCK) ? CaretShape::block : CaretShape::bar;
+	}
+
+	const int caret = caretStyle & CARETSTYLE_INS_MASK;
+	return (caret <= CARETSTYLE_BLOCK) ? static_cast<CaretShape>(caret) : CaretShape::line;
+}
+
 void ViewStyle::AllocStyles(size_t sizeNew) {
 	size_t i=styles.size();
 	styles.resize(sizeNew);
diff --git a/scintilla/src/ViewStyle.h b/scintilla/src/ViewStyle.h
index 800d8cb679..587eb976a8 100644
--- a/scintilla/src/ViewStyle.h
+++ b/scintilla/src/ViewStyle.h
@@ -20,30 +20,17 @@ class MarginStyle {
 	int mask;
 	bool sensitive;
 	int cursor;
-	MarginStyle(int style_= SC_MARGIN_SYMBOL, int width_=0, int mask_=0);
+	MarginStyle(int style_= SC_MARGIN_SYMBOL, int width_=0, int mask_=0) noexcept;
 };
 
 /**
  */
-class FontNames {
-private:
-	std::vector<UniqueString> names;
-public:
-	FontNames();
-	// FontNames objects can not be copied.
-	FontNames(const FontNames &) = delete;
-	FontNames(FontNames &&) = delete;
-	FontNames &operator=(const FontNames &) = delete;
-	FontNames &operator=(FontNames &&) = delete;
-	~FontNames();
-	void Clear();
-	const char *Save(const char *name);
-};
+
 
 class FontRealised : public FontMeasurements {
 public:
 	Font font;
-	FontRealised();
+	FontRealised() noexcept;
 	// FontRealised objects can not be copied.
 	FontRealised(const FontRealised &) = delete;
 	FontRealised(FontRealised &&) = delete;
@@ -66,9 +53,9 @@ enum WrapMode { eWrapNone, eWrapWord, eWrapChar, eWrapWhitespace };
 class ColourOptional : public ColourDesired {
 public:
 	bool isSet;
-	ColourOptional(ColourDesired colour_=ColourDesired(0,0,0), bool isSet_=false) : ColourDesired(colour_), isSet(isSet_) {
+	ColourOptional(ColourDesired colour_=ColourDesired(0,0,0), bool isSet_=false) noexcept : ColourDesired(colour_), isSet(isSet_) {
 	}
-	ColourOptional(uptr_t wParam, sptr_t lParam) : ColourDesired(static_cast<int>(lParam)), isSet(wParam != 0) {
+	ColourOptional(uptr_t wParam, sptr_t lParam) noexcept : ColourDesired(static_cast<int>(lParam)), isSet(wParam != 0) {
 	}
 };
 
@@ -80,10 +67,10 @@ struct ForeBackColours {
 struct EdgeProperties {
 	int column;
 	ColourDesired colour;
-	EdgeProperties(int column_ = 0, ColourDesired colour_ = ColourDesired(0)) :
+	EdgeProperties(int column_ = 0, ColourDesired colour_ = ColourDesired(0)) noexcept :
 		column(column_), colour(colour_) {
 	}
-	EdgeProperties(uptr_t wParam, sptr_t lParam) :
+	EdgeProperties(uptr_t wParam, sptr_t lParam) noexcept :
 		column(static_cast<int>(wParam)), colour(static_cast<int>(lParam)) {
 	}
 };
@@ -91,7 +78,7 @@ struct EdgeProperties {
 /**
  */
 class ViewStyle {
-	FontNames fontNames;
+	UniqueStringSet fontNames;
 	FontMap fonts;
 public:
 	std::vector<Style> styles;
@@ -186,31 +173,35 @@ class ViewStyle {
 	void CalculateMarginWidthAndMask();
 	void Init(size_t stylesSize_=256);
 	void Refresh(Surface &surface, int tabInChars);
-	void ReleaseAllExtendedStyles();
+	void ReleaseAllExtendedStyles() noexcept;
 	int AllocateExtendedStyles(int numberStyles);
 	void EnsureStyle(size_t index);
 	void ResetDefaultStyle();
 	void ClearStyles();
 	void SetStyleFontName(int styleIndex, const char *name);
-	bool ProtectionActive() const;
-	int ExternalMarginWidth() const;
+	bool ProtectionActive() const noexcept;
+	int ExternalMarginWidth() const noexcept;
 	int MarginFromLocation(Point pt) const;
-	bool ValidStyle(size_t styleIndex) const;
+	bool ValidStyle(size_t styleIndex) const noexcept;
 	void CalcLargestMarkerHeight();
-	int GetFrameWidth() const;
-	bool IsLineFrameOpaque(bool caretActive, bool lineContainsCaret) const;
+	int GetFrameWidth() const noexcept;
+	bool IsLineFrameOpaque(bool caretActive, bool lineContainsCaret) const noexcept;
 	ColourOptional Background(int marksOfLine, bool caretActive, bool lineContainsCaret) const;
-	bool SelectionBackgroundDrawn() const;
-	bool WhitespaceBackgroundDrawn() const;
+	bool SelectionBackgroundDrawn() const noexcept;
+	bool WhitespaceBackgroundDrawn() const noexcept;
 	ColourDesired WrapColour() const;
 
-	bool SetWrapState(int wrapState_);
-	bool SetWrapVisualFlags(int wrapVisualFlags_);
-	bool SetWrapVisualFlagsLocation(int wrapVisualFlagsLocation_);
-	bool SetWrapVisualStartIndent(int wrapVisualStartIndent_);
-	bool SetWrapIndentMode(int wrapIndentMode_);
+	bool SetWrapState(int wrapState_) noexcept;
+	bool SetWrapVisualFlags(int wrapVisualFlags_) noexcept;
+	bool SetWrapVisualFlagsLocation(int wrapVisualFlagsLocation_) noexcept;
+	bool SetWrapVisualStartIndent(int wrapVisualStartIndent_) noexcept;
+	bool SetWrapIndentMode(int wrapIndentMode_) noexcept;
+
+	bool WhiteSpaceVisible(bool inIndent) const noexcept;
 
-	bool WhiteSpaceVisible(bool inIndent) const;
+	enum class CaretShape { invisible, line, block, bar };
+	bool IsBlockCaretStyle() const noexcept;
+	CaretShape CaretShapeForMode(bool inOverstrike) const noexcept;
 
 private:
 	void AllocStyles(size_t sizeNew);
diff --git a/scintilla/src/XPM.h b/scintilla/src/XPM.h
index c3c1fc3b36..9ff612d64d 100644
--- a/scintilla/src/XPM.h
+++ b/scintilla/src/XPM.h
@@ -25,10 +25,10 @@ class XPM {
 public:
 	explicit XPM(const char *textForm);
 	explicit XPM(const char *const *linesForm);
-	XPM(const XPM &) = delete;
-	XPM(XPM &&) = delete;
-	XPM &operator=(const XPM &) = delete;
-	XPM &operator=(XPM &&) = delete;
+	XPM(const XPM &) = default;
+	XPM(XPM &&) = default;
+	XPM &operator=(const XPM &) = default;
+	XPM &operator=(XPM &&) = default;
 	~XPM();
 	void Init(const char *textForm);
 	void Init(const char *const *linesForm);
@@ -52,11 +52,10 @@ class RGBAImage {
 public:
 	RGBAImage(int width_, int height_, float scale_, const unsigned char *pixels_);
 	explicit RGBAImage(const XPM &xpm);
-	// Deleted so RGBAImage objects can not be copied.
-	RGBAImage(const RGBAImage &) = delete;
-	RGBAImage(RGBAImage &&) = delete;
-	RGBAImage &operator=(const RGBAImage &) = delete;
-	RGBAImage &operator=(RGBAImage &&) = delete;
+	RGBAImage(const RGBAImage &) = default;
+	RGBAImage(RGBAImage &&) = default;
+	RGBAImage &operator=(const RGBAImage &) = default;
+	RGBAImage &operator=(RGBAImage &&) = default;
 	virtual ~RGBAImage();
 	int GetHeight() const { return height; }
 	int GetWidth() const { return width; }
diff --git a/scintilla/version.txt b/scintilla/version.txt
index 2b7c0b15b0..ab63d70a73 100644
--- a/scintilla/version.txt
+++ b/scintilla/version.txt
@@ -1 +1 @@
-3102
+3104