From bcd69495ce65aa934a9410a23134117f5c60c870 Mon Sep 17 00:00:00 2001
From: David Capello <david@igarastudio.com>
Date: Fri, 19 Mar 2021 18:57:56 -0300
Subject: [PATCH] Fix several issues locating windows with multiple UI windows

We've refactored the code to support locating windows (and popups
windows + hot regions) correctly in both modes: with one ui::Display
and with multiple ui::Displays.

For this we've added a new ui::fit_bounds() function that works in
both modes.
---
 laf                                          |   2 +-
 src/app/commands/cmd_canvas_size.cpp         |  13 ++-
 src/app/commands/cmd_change_pixel_format.cpp |   7 +-
 src/app/commands/cmd_keyboard_shortcuts.cpp  |  15 ++-
 src/app/commands/cmd_paste_text.cpp          |   6 +-
 src/app/console.cpp                          |  17 +--
 src/app/modules/gui.cpp                      |  12 ++-
 src/app/ui/browser_view.cpp                  |   2 +-
 src/app/ui/brush_popup.cpp                   |  35 +++---
 src/app/ui/brush_popup.h                     |   5 +-
 src/app/ui/color_bar.cpp                     |  11 +-
 src/app/ui/color_button.cpp                  |  94 +++++++++++-----
 src/app/ui/color_button.h                    |   7 ++
 src/app/ui/color_wheel.cpp                   |   4 +-
 src/app/ui/context_bar.cpp                   |  36 ++++---
 src/app/ui/data_recovery_view.cpp            |   4 +-
 src/app/ui/devconsole_view.cpp               |   2 +-
 src/app/ui/doc_view.cpp                      |   2 +-
 src/app/ui/dynamics_popup.cpp                |  19 ++--
 src/app/ui/editor/editor.cpp                 |   2 +-
 src/app/ui/editor/standby_state.cpp          |   2 +-
 src/app/ui/font_popup.cpp                    |  17 ++-
 src/app/ui/font_popup.h                      |   4 +-
 src/app/ui/home_view.cpp                     |   2 +-
 src/app/ui/main_window.cpp                   |   8 +-
 src/app/ui/notifications.cpp                 |   8 +-
 src/app/ui/palette_popup.cpp                 |  15 ++-
 src/app/ui/palette_popup.h                   |   4 +-
 src/app/ui/popup_window_pin.cpp              |   6 +-
 src/app/ui/preview_editor.cpp                |  39 +++----
 src/app/ui/status_bar.cpp                    |   2 +
 src/app/ui/timeline/timeline.cpp             |  16 +--
 src/ui/combobox.cpp                          |   2 +-
 src/ui/display.h                             |   1 +
 src/ui/entry.cpp                             |   2 +-
 src/ui/fit_bounds.cpp                        |  49 ++++++++-
 src/ui/fit_bounds.h                          |  22 +++-
 src/ui/int_entry.cpp                         |  37 ++++---
 src/ui/manager.cpp                           |  57 ++++++++--
 src/ui/manager.h                             |   1 +
 src/ui/menu.cpp                              | 106 ++++++++++---------
 src/ui/menu.h                                |   7 +-
 src/ui/popup_window.cpp                      |  26 +++--
 src/ui/popup_window.h                        |  10 +-
 src/ui/widget.cpp                            |  10 ++
 src/ui/widget.h                              |   3 +
 src/ui/window.cpp                            |  21 +++-
 src/ui/window.h                              |   8 +-
 48 files changed, 517 insertions(+), 263 deletions(-)

diff --git a/laf b/laf
index d290eaf37f..1106d7488d 160000
--- a/laf
+++ b/laf
@@ -1 +1 @@
-Subproject commit d290eaf37fcb1a48cee433e6b9a1b73854671df0
+Subproject commit 1106d7488dcf1410815601c9eaa38407bc243893
diff --git a/src/app/commands/cmd_canvas_size.cpp b/src/app/commands/cmd_canvas_size.cpp
index 840108c10e..53d9e361e9 100644
--- a/src/app/commands/cmd_canvas_size.cpp
+++ b/src/app/commands/cmd_canvas_size.cpp
@@ -342,12 +342,17 @@ void CanvasSizeCommand::onExecute(Context* context)
 
     // Find best position for the window on the editor
     if (DocView* docView = static_cast<UIContext*>(context)->activeView()) {
-      window->positionWindow(
-        docView->bounds().x2() - window->bounds().w,
-        docView->bounds().y);
+      Display* display = ui::Manager::getDefault()->display();
+      ui::fit_bounds(display,
+                     window.get(),
+                     gfx::Rect(docView->bounds().x2() - window->bounds().w,
+                               docView->bounds().y,
+                               window->bounds().w,
+                               window->bounds().h));
     }
-    else
+    else {
       window->centerWindow();
+    }
 
     load_window_pos(window.get(), "CanvasSize");
     window->setVisible(true);
diff --git a/src/app/commands/cmd_change_pixel_format.cpp b/src/app/commands/cmd_change_pixel_format.cpp
index 09bb0ae1a7..138dcf0831 100644
--- a/src/app/commands/cmd_change_pixel_format.cpp
+++ b/src/app/commands/cmd_change_pixel_format.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2019-2020  Igara Studio S.A.
+// Copyright (C) 2019-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -246,10 +246,7 @@ class ColorModeWindow : public app::gen::ColorMode {
       advancedCheck()->Click.connect(
         [this](ui::Event&){
           advanced()->setVisible(advancedCheck()->isSelected());
-
-          const gfx::Rect origBounds = bounds();
-          setBounds(gfx::Rect(bounds().origin(), sizeHint()));
-          manager()->invalidateRect(origBounds);
+          expandWindow(sizeHint());
         });
     }
     else {
diff --git a/src/app/commands/cmd_keyboard_shortcuts.cpp b/src/app/commands/cmd_keyboard_shortcuts.cpp
index 56df8062ee..1c56f0acac 100644
--- a/src/app/commands/cmd_keyboard_shortcuts.cpp
+++ b/src/app/commands/cmd_keyboard_shortcuts.cpp
@@ -32,6 +32,7 @@
 #include "base/string.h"
 #include "fmt/format.h"
 #include "ui/alert.h"
+#include "ui/fit_bounds.h"
 #include "ui/graphics.h"
 #include "ui/listitem.h"
 #include "ui/message.h"
@@ -882,11 +883,19 @@ void KeyboardShortcutsCommand::onExecute(Context* context)
   std::string neededSearchCopy = m_search;
   KeyboardShortcutsWindow window(keys, menuKeys, neededSearchCopy);
 
-  gfx::Size displaySize = ui::get_desktop_size();
-  window.setBounds(gfx::Rect(0, 0, displaySize.w*3/4, displaySize.h*3/4));
+  ui::Display* mainDisplay = Manager::getDefault()->display();
+  ui::fit_bounds(mainDisplay, &window,
+                 gfx::Rect(mainDisplay->size()),
+                 [](const gfx::Rect& workarea,
+                    gfx::Rect& bounds,
+                    std::function<gfx::Rect(Widget*)> getWidgetBounds) {
+                   gfx::Point center = bounds.center();
+                   bounds.setSize(workarea.size()*3/4);
+                   bounds.setOrigin(center - gfx::Point(bounds.size()/2));
+                 });
+
   window.loadLayout();
 
-  window.centerWindow();
   window.setVisible(true);
   window.openWindowInForeground();
 
diff --git a/src/app/commands/cmd_paste_text.cpp b/src/app/commands/cmd_paste_text.cpp
index 1619fc7404..5b6d308ac9 100644
--- a/src/app/commands/cmd_paste_text.cpp
+++ b/src/app/commands/cmd_paste_text.cpp
@@ -124,11 +124,7 @@ class PasteTextWindow : public app::gen::PasteText {
     }
 
     if (!m_fontPopup->isVisible()) {
-      gfx::Size displaySize = manager()->display()->size();
-      gfx::Rect bounds = fontFace()->bounds();
-      m_fontPopup->showPopup(
-        gfx::Rect(bounds.x, bounds.y+bounds.h,
-                  displaySize.w/2, displaySize.h/2));
+      m_fontPopup->showPopup(display(), fontFace()->bounds());
     }
     else {
       m_fontPopup->closeWindow(NULL);
diff --git a/src/app/console.cpp b/src/app/console.cpp
index 2429042326..7d0804d915 100644
--- a/src/app/console.cpp
+++ b/src/app/console.cpp
@@ -71,14 +71,15 @@ class Console::ConsoleWindow : public Window {
   void centerConsole() {
     initTheme();
 
-    remapWindow();
-
-    // TODO center to main window or screen workspace
-    gfx::Size displaySize = manager()->display()->size();
-    setBounds(gfx::Rect(0, 0, displaySize.w*9/10, displaySize.h*6/10));
-
-    centerWindow();
-    invalidate();
+    Display* display = ui::Manager::getDefault()->display();
+    const gfx::Rect displayRc = display->bounds();
+    gfx::Rect rc;
+    rc.w = displayRc.w*9/10;
+    rc.h = displayRc.h*6/10;
+    rc.x = displayRc.x + displayRc.w/2 - rc.w/2;
+    rc.y = displayRc.y + displayRc.h/2 - rc.h/2;
+
+    ui::fit_bounds(display, this, rc);
   }
 
 private:
diff --git a/src/app/modules/gui.cpp b/src/app/modules/gui.cpp
index 47b5cd36e0..11ed312b2e 100644
--- a/src/app/modules/gui.cpp
+++ b/src/app/modules/gui.cpp
@@ -693,11 +693,15 @@ void CustomizedGuiManager::onInitTheme(InitThemeEvent& ev)
 void CustomizedGuiManager::onNewDisplayConfiguration(Display* display)
 {
   Manager::onNewDisplayConfiguration(display);
-  save_gui_config();
 
-  // TODO Should we provide a more generic way for all ui::Window to
-  //      detect the os::Window (or UI Screen Scaling) change?
-  Console::notifyNewDisplayConfiguration();
+  // Only whne the main display/window is modified
+  if (display == this->display()) {
+    save_gui_config();
+
+    // TODO Should we provide a more generic way for all ui::Window to
+    //      detect the os::Window (or UI Screen Scaling) change?
+    Console::notifyNewDisplayConfiguration();
+  }
 }
 
 std::string CustomizedGuiManager::loadLayout(Widget* widget)
diff --git a/src/app/ui/browser_view.cpp b/src/app/ui/browser_view.cpp
index 0e22a1bb85..22bc63bc31 100644
--- a/src/app/ui/browser_view.cpp
+++ b/src/app/ui/browser_view.cpp
@@ -589,7 +589,7 @@ void BrowserView::onTabPopup(Workspace* workspace)
   if (!menu)
     return;
 
-  menu->showPopup(mousePosInDisplay());
+  menu->showPopup(mousePosInDisplay(), display());
 }
 
 } // namespace app
diff --git a/src/app/ui/brush_popup.cpp b/src/app/ui/brush_popup.cpp
index 63d78df548..403d32b098 100644
--- a/src/app/ui/brush_popup.cpp
+++ b/src/app/ui/brush_popup.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -36,6 +36,7 @@
 #include "os/surface.h"
 #include "os/system.h"
 #include "ui/button.h"
+#include "ui/fit_bounds.h"
 #include "ui/link_label.h"
 #include "ui/listitem.h"
 #include "ui/menu.h"
@@ -52,22 +53,24 @@ using namespace ui;
 
 namespace {
 
-void show_popup_menu(PopupWindow* popupWindow, Menu* popupMenu,
-                     const gfx::Point& pt)
+void show_popup_menu(PopupWindow* popupWindow,
+                     Menu* popupMenu,
+                     const gfx::Point& pt,
+                     Display* display)
 {
   // Here we make the popup window temporaly floating, so it's
   // not closed by the popup menu.
   popupWindow->makeFloating();
 
-  popupMenu->showPopup(pt);
+  popupMenu->showPopup(pt, display);
 
   // Add the menu popup region to the window popup hot region so it's
   // not closed after we close the menu.
   popupWindow->makeFixed();
 
   gfx::Region rgn;
-  rgn.createUnion(gfx::Region(popupWindow->bounds()),
-                  gfx::Region(popupMenu->bounds()));
+  rgn.createUnion(gfx::Region(popupWindow->boundsOnScreen()),
+                  gfx::Region(popupMenu->boundsOnScreen()));
   popupWindow->setHotRegion(rgn);
 }
 
@@ -194,7 +197,8 @@ class BrushOptionsItem : public ButtonSet::Item {
 
     m_changeFlags = true;
     show_popup_menu(m_popup, &menu,
-                    gfx::Point(origin().x, origin().y+bounds().h));
+                    gfx::Point(origin().x, origin().y+bounds().h),
+                    display());
 
     if (m_changeFlags) {
       brush = m_brushes.getBrushSlot(m_slot);
@@ -299,8 +303,10 @@ class NewBrushOptionsItem : public ButtonSet::Item {
     params.shade()->setSelected(saveBrush.shade());
     params.pixelPerfect()->setSelected(saveBrush.pixelPerfect());
 
-    show_popup_menu(static_cast<PopupWindow*>(window()), &menu,
-                    gfx::Point(origin().x, origin().y+bounds().h));
+    show_popup_menu(static_cast<PopupWindow*>(window()),
+                    &menu,
+                    gfx::Point(origin().x, origin().y+bounds().h),
+                    display());
 
     // Save preferences
     if (saveBrush.brushType() != params.brushType()->isSelected())
@@ -384,7 +390,8 @@ void BrushPopup::setBrush(Brush* brush)
   }
 }
 
-void BrushPopup::regenerate(const gfx::Rect& box)
+void BrushPopup::regenerate(ui::Display* display,
+                            const gfx::Point& pos)
 {
   auto& brushSlots = App::instance()->brushes().getBrushSlots();
 
@@ -425,8 +432,8 @@ void BrushPopup::regenerate(const gfx::Rect& box)
   m_box.addChild(m_customBrushes);
 
   // Resize the window and change the hot region.
-  setBounds(gfx::Rect(box.origin(), sizeHint()));
-  setHotRegion(gfx::Region(bounds()));
+  fit_bounds(display, this, gfx::Rect(pos, sizeHint()));
+  setHotRegion(gfx::Region(boundsOnScreen()));
 }
 
 void BrushPopup::onBrushChanges()
@@ -435,7 +442,9 @@ void BrushPopup::onBrushChanges()
     gfx::Region rgn;
     getDrawableRegion(rgn, kCutTopWindowsAndUseChildArea);
 
-    regenerate(bounds());
+    Display* mainDisplay = manager()->display();
+    regenerate(mainDisplay,
+               mainDisplay->nativeWindow()->pointFromScreen(boundsOnScreen().origin()));
     invalidate();
 
     parent()->invalidateRegion(rgn);
diff --git a/src/app/ui/brush_popup.h b/src/app/ui/brush_popup.h
index a5dc1af770..34d79f046c 100644
--- a/src/app/ui/brush_popup.h
+++ b/src/app/ui/brush_popup.h
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2001-2015  David Capello
 //
 // This program is distributed under the terms of
@@ -21,7 +21,8 @@ namespace app {
     BrushPopup();
 
     void setBrush(doc::Brush* brush);
-    void regenerate(const gfx::Rect& box);
+    void regenerate(ui::Display* display,
+                    const gfx::Point& pos);
 
     static os::SurfaceRef createSurfaceForBrush(const doc::BrushRef& brush);
 
diff --git a/src/app/ui/color_bar.cpp b/src/app/ui/color_bar.cpp
index 40db5d3917..9c1eeef01b 100644
--- a/src/app/ui/color_bar.cpp
+++ b/src/app/ui/color_bar.cpp
@@ -1868,7 +1868,7 @@ void ColorBar::showPaletteSortOptions()
   asc.Click.connect([this]{ setAscending(true); });
   des.Click.connect([this]{ setAscending(false); });
 
-  menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+  menu.showPopup(gfx::Point(bounds.x, bounds.y2()), display());
 }
 
 void ColorBar::showPalettePresets()
@@ -1884,16 +1884,13 @@ void ColorBar::showPalettePresets()
   }
 
   if (!m_palettePopup->isVisible()) {
-    gfx::Size displaySize = ui::get_desktop_size();
     gfx::Rect bounds = m_buttons.getItem(
       static_cast<int>(PalButton::PRESETS))->bounds();
 
-    m_palettePopup->showPopup(
-      gfx::Rect(bounds.x, bounds.y+bounds.h,
-                displaySize.w/2, displaySize.h*3/4));
+    m_palettePopup->showPopup(display(), bounds);
   }
   else {
-    m_palettePopup->closeWindow(NULL);
+    m_palettePopup->closeWindow(nullptr);
   }
 }
 
@@ -1904,7 +1901,7 @@ void ColorBar::showPaletteOptions()
     gfx::Rect bounds = m_buttons.getItem(
       static_cast<int>(PalButton::OPTIONS))->bounds();
 
-    menu->showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+    menu->showPopup(gfx::Point(bounds.x, bounds.y2()), display());
   }
 }
 
diff --git a/src/app/ui/color_button.cpp b/src/app/ui/color_button.cpp
index 8546701232..c3102192b6 100644
--- a/src/app/ui/color_button.cpp
+++ b/src/app/ui/color_button.cpp
@@ -53,6 +53,7 @@ ColorButton::ColorButton(const app::Color& color,
   , m_color(color)
   , m_pixelFormat(pixelFormat)
   , m_window(nullptr)
+  , m_desktopCoords(false)
   , m_dependOnLayer(false)
   , m_options(options)
 {
@@ -306,9 +307,12 @@ void ColorButton::onLoadLayout(ui::LoadLayoutEvent& ev)
 {
   if (canPin()) {
     bool pinned = false;
+
+    m_desktopCoords = false;
     ev.stream() >> pinned;
     if (ev.stream() && pinned)
-      ev.stream() >> m_windowDefaultBounds;
+      ev.stream() >> m_windowDefaultBounds
+                  >> m_desktopCoords;
 
     m_hiddenPopupBounds = m_windowDefaultBounds;
   }
@@ -316,8 +320,12 @@ void ColorButton::onLoadLayout(ui::LoadLayoutEvent& ev)
 
 void ColorButton::onSaveLayout(ui::SaveLayoutEvent& ev)
 {
-  if (canPin() && m_window && m_window->isPinned())
-    ev.stream() << 1 << ' ' << m_window->bounds();
+  if (canPin() && m_window && m_window->isPinned()) {
+    if (m_desktopCoords)
+      ev.stream() << 1 << ' ' << m_window->lastNativeFrame() << ' ' << 1;
+    else
+      ev.stream() << 1 << ' ' << m_window->bounds() << ' ' << 0;
+  }
   else
     ev.stream() << 0;
 }
@@ -339,37 +347,39 @@ void ColorButton::openPopup(const bool forcePinned)
   }
 
   m_window->setColor(m_color, ColorPopup::ChangeType);
-  m_window->openWindow();
-
-  gfx::Size displaySize = ui::get_desktop_size();
-  gfx::Rect winBounds;
-  if (!pinned || (forcePinned && m_hiddenPopupBounds.isEmpty())) {
-    winBounds = gfx::Rect(m_window->bounds().origin(),
-                          m_window->sizeHint());
-    winBounds.x = base::clamp(bounds().x, 0, displaySize.w-winBounds.w);
-    if (bounds().y2() <= displaySize.h-winBounds.h)
-      winBounds.y = std::max(0, bounds().y2());
-    else
-      winBounds.y = std::max(0, bounds().y-winBounds.h);
-  }
-  else if (forcePinned) {
-    winBounds = m_hiddenPopupBounds;
-  }
-  else {
-    winBounds = m_windowDefaultBounds;
-  }
-  winBounds.x = base::clamp(winBounds.x, 0, displaySize.w-winBounds.w);
-  winBounds.y = base::clamp(winBounds.y, 0, displaySize.h-winBounds.h);
-  m_window->setBounds(winBounds);
+  m_window->remapWindow();
+
+  fit_bounds(
+    display(),
+    m_window,
+    gfx::Rect(m_window->sizeHint()),
+    [this, pinned, forcePinned](const gfx::Rect& workarea,
+                                gfx::Rect& winBounds,
+                                std::function<gfx::Rect(Widget*)> getWidgetBounds) {
+      if (!pinned || (forcePinned && m_hiddenPopupBounds.isEmpty())) {
+        gfx::Rect bounds = getWidgetBounds(this);
+
+        winBounds.x = base::clamp(bounds.x, workarea.x, workarea.x2()-winBounds.w);
+        if (bounds.y2()+winBounds.h <= workarea.y2())
+          winBounds.y = std::max(0, bounds.y2());
+        else
+          winBounds.y = std::max(0, bounds.y-winBounds.h);
+      }
+      else if (forcePinned) {
+        winBounds = convertBounds(m_hiddenPopupBounds);
+      }
+      else {
+        winBounds = convertBounds(m_windowDefaultBounds);
+      }
+    });
 
-  m_window->manager()->dispatchMessages();
-  m_window->layout();
+  m_window->openWindow();
 
   m_window->setPinned(pinned);
 
   // Add the ColorButton area to the ColorPopup hot-region
   if (!pinned) {
-    gfx::Rect rc = bounds().createUnion(m_window->bounds());
+    gfx::Rect rc = boundsOnScreen().createUnion(m_window->boundsOnScreen());
     rc.enlarge(8);
     gfx::Region rgn(rc);
     static_cast<PopupWindow*>(m_window)->setHotRegion(rgn);
@@ -386,7 +396,14 @@ void ColorButton::closePopup()
 
 void ColorButton::onWindowClose(ui::CloseEvent& ev)
 {
-  m_hiddenPopupBounds = m_window->bounds();
+  if (get_multiple_displays()) {
+    m_desktopCoords = true;
+    m_hiddenPopupBounds = m_window->lastNativeFrame();
+  }
+  else {
+    m_desktopCoords = false;
+    m_hiddenPopupBounds = m_window->bounds();
+  }
 }
 
 void ColorButton::onWindowColorChange(const app::Color& color)
@@ -418,4 +435,23 @@ void ColorButton::onActiveSiteChange(const Site& site)
   }
 }
 
+gfx::Rect ColorButton::convertBounds(const gfx::Rect& bounds) const
+{
+  // Convert to desktop
+  if (get_multiple_displays() && !m_desktopCoords) {
+    auto nativeWindow = display()->nativeWindow();
+    return gfx::Rect(nativeWindow->pointToScreen(bounds.origin()),
+                     nativeWindow->pointToScreen(bounds.point2()));
+  }
+  // Convert to display
+  else if (!get_multiple_displays() && m_desktopCoords) {
+    auto nativeWindow = display()->nativeWindow();
+    return gfx::Rect(nativeWindow->pointFromScreen(bounds.origin()),
+                     nativeWindow->pointFromScreen(bounds.point2()));
+  }
+  // No conversion is required
+  else
+    return bounds;
+}
+
 } // namespace app
diff --git a/src/app/ui/color_button.h b/src/app/ui/color_button.h
index f55b7ab310..6fe9ba3e8c 100644
--- a/src/app/ui/color_button.h
+++ b/src/app/ui/color_button.h
@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -68,11 +69,17 @@ namespace app {
     void onWindowColorChange(const app::Color& color);
     bool canPin() const { return m_options.canPinSelector; }
 
+    // Used to convert saved bounds (m_window/hiddenDefaultBounds,
+    // which can be relative to the display or relative to the screen)
+    // to the current system of coordinates.
+    gfx::Rect convertBounds(const gfx::Rect& bounds) const;
+
     app::Color m_color;
     PixelFormat m_pixelFormat;
     ColorPopup* m_window;
     gfx::Rect m_windowDefaultBounds;
     gfx::Rect m_hiddenPopupBounds;
+    bool m_desktopCoords;       // True if m_windowDefault/hiddenPopupBounds are screen coordinates
     bool m_dependOnLayer;
     ColorButtonOptions m_options;
   };
diff --git a/src/app/ui/color_wheel.cpp b/src/app/ui/color_wheel.cpp
index df5a2757a4..684fdcc3e1 100644
--- a/src/app/ui/color_wheel.cpp
+++ b/src/app/ui/color_wheel.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -412,7 +412,7 @@ void ColorWheel::onOptions()
   }
 
   gfx::Rect rc = m_options.bounds();
-  menu.showPopup(gfx::Point(rc.x+rc.w, rc.y));
+  menu.showPopup(gfx::Point(rc.x2(), rc.y), display());
 }
 
 int ColorWheel::convertHueAngle(int hue, int dir) const
diff --git a/src/app/ui/context_bar.cpp b/src/app/ui/context_bar.cpp
index a67a5ab5ab..64ce77e343 100644
--- a/src/app/ui/context_bar.cpp
+++ b/src/app/ui/context_bar.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -66,6 +66,7 @@
 #include "render/ordered_dither.h"
 #include "ui/button.h"
 #include "ui/combobox.h"
+#include "ui/fit_bounds.h"
 #include "ui/int_entry.h"
 #include "ui/label.h"
 #include "ui/listbox.h"
@@ -209,20 +210,19 @@ class ContextBar::BrushTypeField : public ButtonSet {
 private:
   // Returns a little rectangle that can be used by the popup as the
   // first brush position.
-  gfx::Rect getPopupBox() {
+  gfx::Point popupPosCandidate() const {
     Rect rc = bounds();
     rc.y += rc.h - 2*guiscale();
-    rc.setSize(sizeHint());
-    return rc;
+    return rc.origin();
   }
 
   void openPopup() {
     doc::BrushRef brush = m_owner->activeBrush();
 
-    m_popupWindow.regenerate(getPopupBox());
+    m_popupWindow.regenerate(display(), popupPosCandidate());
     m_popupWindow.setBrush(brush.get());
 
-    Region rgn(m_popupWindow.bounds().createUnion(bounds()));
+    Region rgn(m_popupWindow.boundsOnScreen().createUnion(boundsOnScreen()));
     m_popupWindow.setHotRegion(rgn);
 
     m_popupWindow.openWindow();
@@ -450,7 +450,8 @@ class ContextBar::PaintBucketSettingsField : public ButtonSet {
         }
       });
 
-    menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+    menu.showPopup(gfx::Point(bounds.x, bounds.y2()),
+                   display());
     deselectItems();
   }
 
@@ -502,7 +503,8 @@ class ContextBar::InkTypeField : public ButtonSet {
 
     AppMenus::instance()
       ->getInkPopupMenu()
-      ->showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+      ->showPopup(gfx::Point(bounds.x, bounds.y2()),
+                  display());
 
     deselectItems();
   }
@@ -627,7 +629,8 @@ class ContextBar::InkShadesField : public HBox {
       }
     }
 
-    menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+    menu.showPopup(gfx::Point(bounds.x, bounds.y2()),
+                   display());
     m_button.invalidate();
   }
 
@@ -808,7 +811,8 @@ class ContextBar::TransparentColorField : public HBox {
     masked.Click.connect([this]{ setOpaque(false); });
     automatic.Click.connect([this]{ onAutomatic(); });
 
-    menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+    menu.showPopup(gfx::Point(bounds.x, bounds.y2()),
+                   display());
   }
 
   void onChangeColor() {
@@ -905,7 +909,8 @@ class ContextBar::PivotField : public ButtonSet {
           app::gen::PivotPosition(buttonset.selectedItem()));
       });
 
-    menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+    menu.showPopup(gfx::Point(bounds.x, bounds.y2()),
+                   display());
   }
 
   void onPivotChange() {
@@ -1151,8 +1156,10 @@ class ContextBar::DynamicsField : public ButtonSet
 
     const gfx::Rect bounds = this->bounds();
     m_popup->remapWindow();
-    m_popup->positionWindow(bounds.x, bounds.y+bounds.h);
-    m_popup->setHotRegion(gfx::Region(m_popup->bounds()));
+    fit_bounds(display(), m_popup.get(),
+               gfx::Rect(gfx::Point(bounds.x, bounds.y2()),
+                         m_popup->sizeHint()));
+    m_popup->setHotRegion(gfx::Region(m_popup->boundsOnScreen()));
     m_popup->openWindow();
   }
 
@@ -1436,7 +1443,8 @@ class ContextBar::SymmetryField : public ButtonSet {
           doc->notifyGeneralUpdate();
         });
 
-      menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+      menu.showPopup(gfx::Point(bounds.x, bounds.y2()),
+                     display());
     }
   }
 };
diff --git a/src/app/ui/data_recovery_view.cpp b/src/app/ui/data_recovery_view.cpp
index 86dda5e5a7..94dd0fad60 100644
--- a/src/app/ui/data_recovery_view.cpp
+++ b/src/app/ui/data_recovery_view.cpp
@@ -413,7 +413,7 @@ void DataRecoveryView::onTabPopup(Workspace* workspace)
   if (!menu)
     return;
 
-  menu->showPopup(mousePosInDisplay());
+  menu->showPopup(mousePosInDisplay(), display());
 }
 
 void DataRecoveryView::onOpen()
@@ -461,7 +461,7 @@ void DataRecoveryView::onOpenMenu()
   rawFrames.Click.connect([this]{ onOpenRaw(crash::RawImagesAs::kFrames); });
   rawLayers.Click.connect([this]{ onOpenRaw(crash::RawImagesAs::kLayers); });
 
-  menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h));
+  menu.showPopup(gfx::Point(bounds.x, bounds.y+bounds.h), display());
 }
 
 void DataRecoveryView::onDelete()
diff --git a/src/app/ui/devconsole_view.cpp b/src/app/ui/devconsole_view.cpp
index 0ef400e046..d6a5b580bf 100644
--- a/src/app/ui/devconsole_view.cpp
+++ b/src/app/ui/devconsole_view.cpp
@@ -140,7 +140,7 @@ void DevConsoleView::onTabPopup(Workspace* workspace)
   if (!menu)
     return;
 
-  menu->showPopup(mousePosInDisplay());
+  menu->showPopup(mousePosInDisplay(), display());
 }
 
 bool DevConsoleView::onProcessMessage(Message* msg)
diff --git a/src/app/ui/doc_view.cpp b/src/app/ui/doc_view.cpp
index e623797392..d5449f4f5e 100644
--- a/src/app/ui/doc_view.cpp
+++ b/src/app/ui/doc_view.cpp
@@ -362,7 +362,7 @@ void DocView::onTabPopup(Workspace* workspace)
   ctx->setActiveView(this);
   ctx->updateFlags();
 
-  menu->showPopup(mousePosInDisplay());
+  menu->showPopup(mousePosInDisplay(), display());
 }
 
 bool DocView::onProcessMessage(Message* msg)
diff --git a/src/app/ui/dynamics_popup.cpp b/src/app/ui/dynamics_popup.cpp
index 72cd9871ac..9e89bedc9d 100644
--- a/src/app/ui/dynamics_popup.cpp
+++ b/src/app/ui/dynamics_popup.cpp
@@ -370,15 +370,10 @@ void DynamicsPopup::onValuesChange(ButtonSet::Item* item)
   m_dynamics->velocityLabel()->setVisible(hasVelocity);
   m_dynamics->velocityPlaceholder()->setVisible(hasVelocity);
 
-  auto oldBounds = bounds();
-  layout();
-  setBounds(gfx::Rect(origin(), sizeHint()));
+  expandWindow(sizeHint());
 
-  m_hotRegion |= gfx::Region(bounds());
+  m_hotRegion |= gfx::Region(boundsOnScreen());
   setHotRegion(m_hotRegion);
-
-  if (isVisible())
-    manager()->invalidateRect(oldBounds);
 }
 
 void DynamicsPopup::updateFromToText()
@@ -400,7 +395,7 @@ bool DynamicsPopup::onProcessMessage(Message* msg)
   switch (msg->type()) {
 
     case kOpenMessage:
-      m_hotRegion = gfx::Region(bounds());
+      m_hotRegion = gfx::Region(boundsOnScreen());
       setHotRegion(m_hotRegion);
       manager()->addMessageFilter(kMouseMoveMessage, this);
       manager()->addMessageFilter(kMouseDownMessage, this);
@@ -442,8 +437,13 @@ bool DynamicsPopup::onProcessMessage(Message* msg)
     }
 
     case kMouseDownMessage: {
+      if (!msg->display())
+        break;
+
+      os::Window* nativeWindow = msg->display()->nativeWindow();
       auto mouseMsg = static_cast<MouseMessage*>(msg);
-      auto picked = manager()->pick(mouseMsg->position());
+      auto screenPos = nativeWindow->pointToScreen(mouseMsg->position());
+      auto picked = manager()->pickFromScreenPos(screenPos);
       if ((picked == nullptr) ||
           (picked->window() != this &&
            picked->window() != m_ditheringSel->getWindowWidget())) {
@@ -451,6 +451,7 @@ bool DynamicsPopup::onProcessMessage(Message* msg)
       }
       break;
     }
+
   }
   return PopupWindow::onProcessMessage(msg);
 }
diff --git a/src/app/ui/editor/editor.cpp b/src/app/ui/editor/editor.cpp
index 42078212ed..9cf9a4fd4b 100644
--- a/src/app/ui/editor/editor.cpp
+++ b/src/app/ui/editor/editor.cpp
@@ -2754,7 +2754,7 @@ void Editor::showAnimationSpeedMultiplierPopup(Option<bool>& playOnce,
     menu.addChild(item);
   }
 
-  menu.showPopup(mousePosInDisplay());
+  menu.showPopup(mousePosInDisplay(), display());
 
   if (isPlaying()) {
     // Re-play
diff --git a/src/app/ui/editor/standby_state.cpp b/src/app/ui/editor/standby_state.cpp
index e57f10b4fd..b23cb75080 100644
--- a/src/app/ui/editor/standby_state.cpp
+++ b/src/app/ui/editor/standby_state.cpp
@@ -256,7 +256,7 @@ bool StandbyState::onMouseDown(Editor* editor, MouseMessage* msg)
             if (!editor->hasSelectedSlices())
               params.set("id", base::convert_to<std::string>(hit.slice()->id()).c_str());
             AppMenuItem::setContextParams(params);
-            popupMenu->showPopup(msg->position());
+            popupMenu->showPopup(msg->position(), editor->display());
             AppMenuItem::setContextParams(Params());
           }
         }
diff --git a/src/app/ui/font_popup.cpp b/src/app/ui/font_popup.cpp
index 4bdf44457b..c251c17d7f 100644
--- a/src/app/ui/font_popup.cpp
+++ b/src/app/ui/font_popup.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -29,6 +29,7 @@
 #include "os/system.h"
 #include "ui/box.h"
 #include "ui/button.h"
+#include "ui/fit_bounds.h"
 #include "ui/graphics.h"
 #include "ui/listitem.h"
 #include "ui/paint_event.h"
@@ -183,15 +184,23 @@ FontPopup::FontPopup()
     m_listBox.addChild(new ListItem("No system fonts were found"));
 }
 
-void FontPopup::showPopup(const gfx::Rect& bounds)
+void FontPopup::showPopup(Display* display,
+                          const gfx::Rect& buttonBounds)
 {
   m_popup->loadFont()->setEnabled(false);
   m_listBox.selectChild(NULL);
 
-  moveWindow(bounds);
+  ui::fit_bounds(display, this,
+                 gfx::Rect(buttonBounds.x, buttonBounds.y2(), 32, 32),
+                 [](const gfx::Rect& workarea,
+                    gfx::Rect& bounds,
+                    std::function<gfx::Rect(Widget*)> getWidgetBounds) {
+                   bounds.w = workarea.w / 2;
+                   bounds.h = workarea.h / 2;
+                 });
 
   // Setup the hot-region
-  setHotRegion(gfx::Region(gfx::Rect(bounds).enlarge(32 * guiscale())));
+  setHotRegion(gfx::Region(gfx::Rect(boundsOnScreen()).enlarge(32*guiscale()*display->scale())));
 
   openWindow();
 }
diff --git a/src/app/ui/font_popup.h b/src/app/ui/font_popup.h
index 2e51371d44..c9372d0b7d 100644
--- a/src/app/ui/font_popup.h
+++ b/src/app/ui/font_popup.h
@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This program is distributed under the terms of
@@ -26,7 +27,8 @@ namespace app {
   public:
     FontPopup();
 
-    void showPopup(const gfx::Rect& bounds);
+    void showPopup(ui::Display* display,
+                   const gfx::Rect& buttonBounds);
 
     obs::signal<void(const std::string&)> Load;
 
diff --git a/src/app/ui/home_view.cpp b/src/app/ui/home_view.cpp
index 5136cb55aa..b4f2d59be2 100644
--- a/src/app/ui/home_view.cpp
+++ b/src/app/ui/home_view.cpp
@@ -136,7 +136,7 @@ void HomeView::onTabPopup(Workspace* workspace)
   if (!menu)
     return;
 
-  menu->showPopup(mousePosInDisplay());
+  menu->showPopup(mousePosInDisplay(), display());
 }
 
 void HomeView::onWorkspaceViewSelected()
diff --git a/src/app/ui/main_window.cpp b/src/app/ui/main_window.cpp
index 50b108d8ab..3322474dbd 100644
--- a/src/app/ui/main_window.cpp
+++ b/src/app/ui/main_window.cpp
@@ -40,7 +40,6 @@
 #include "app/ui_context.h"
 #include "base/fs.h"
 #include "os/system.h"
-#include "os/window.h"
 #include "ui/message.h"
 #include "ui/splitter.h"
 #include "ui/system.h"
@@ -368,13 +367,12 @@ void MainWindow::onResize(ui::ResizeEvent& ev)
 {
   app::gen::MainWindow::onResize(ev);
 
-  gfx::Size desktopSize = ui::get_desktop_size();
   ui::Display* display = this->display();
   if ((display) &&
-      (display->nativeWindow()->scale()*ui::guiscale() > 2) &&
+      (display->scale()*ui::guiscale() > 2) &&
       (!m_scalePanic) &&
-      (desktopSize.w/ui::guiscale() < 320 ||
-       desktopSize.h/ui::guiscale() < 260)) {
+      (display->size().w / ui::guiscale() < 320 ||
+       display->size().h / ui::guiscale() < 260)) {
     showNotification(m_scalePanic = new ScreenScalePanic);
   }
 }
diff --git a/src/app/ui/notifications.cpp b/src/app/ui/notifications.cpp
index 95eb3263d0..4b6b857b9b 100644
--- a/src/app/ui/notifications.cpp
+++ b/src/app/ui/notifications.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This program is distributed under the terms of
@@ -76,9 +76,11 @@ void Notifications::onClick(ui::Event& ev)
   invalidate();
 
   gfx::Rect bounds = this->bounds();
-  m_popup.showPopup(gfx::Point(
+  m_popup.showPopup(
+    gfx::Point(
       bounds.x - m_popup.sizeHint().w,
-      bounds.y + bounds.h));
+      bounds.y2()),
+    display());
 }
 
 } // namespace app
diff --git a/src/app/ui/palette_popup.cpp b/src/app/ui/palette_popup.cpp
index 39a831cfef..1b80e1df70 100644
--- a/src/app/ui/palette_popup.cpp
+++ b/src/app/ui/palette_popup.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -22,6 +22,7 @@
 #include "app/ui_context.h"
 #include "ui/box.h"
 #include "ui/button.h"
+#include "ui/fit_bounds.h"
 #include "ui/scale.h"
 #include "ui/theme.h"
 #include "ui/view.h"
@@ -58,13 +59,21 @@ PalettePopup::PalettePopup()
   initTheme();
 }
 
-void PalettePopup::showPopup(const gfx::Rect& bounds)
+void PalettePopup::showPopup(ui::Display* display,
+                             const gfx::Rect& buttonPos)
 {
   m_popup->loadPal()->setEnabled(false);
   m_popup->openFolder()->setEnabled(false);
   m_paletteListBox.selectChild(NULL);
 
-  moveWindow(bounds);
+  fit_bounds(display, this,
+             gfx::Rect(buttonPos.x, buttonPos.y2(), 32, 32),
+             [](const gfx::Rect& workarea,
+                gfx::Rect& bounds,
+                std::function<gfx::Rect(Widget*)> getWidgetBounds) {
+               bounds.w = workarea.w/2;
+               bounds.h = workarea.h*3/4;
+             });
 
   openWindowInForeground();
 }
diff --git a/src/app/ui/palette_popup.h b/src/app/ui/palette_popup.h
index a4f63ee5be..c1d75a0026 100644
--- a/src/app/ui/palette_popup.h
+++ b/src/app/ui/palette_popup.h
@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This program is distributed under the terms of
@@ -26,7 +27,8 @@ namespace app {
   public:
     PalettePopup();
 
-    void showPopup(const gfx::Rect& bounds);
+    void showPopup(ui::Display* display,
+                   const gfx::Rect& buttonPos);
 
   protected:
     void onPalChange(doc::Palette* palette);
diff --git a/src/app/ui/popup_window_pin.cpp b/src/app/ui/popup_window_pin.cpp
index 597b51f96b..badebde0e8 100644
--- a/src/app/ui/popup_window_pin.cpp
+++ b/src/app/ui/popup_window_pin.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This program is distributed under the terms of
@@ -40,8 +40,8 @@ void PopupWindowPin::setPinned(const bool pinned)
   if (m_pinned)
     makeFloating();
   else {
-    gfx::Rect rc = bounds();
-    rc.enlarge(8);
+    gfx::Rect rc = boundsOnScreen();
+    rc.enlarge(8 * guiscale());
     setHotRegion(gfx::Region(rc));
     makeFixed();
   }
diff --git a/src/app/ui/preview_editor.cpp b/src/app/ui/preview_editor.cpp
index 4759c72f54..f8ab781ee8 100644
--- a/src/app/ui/preview_editor.cpp
+++ b/src/app/ui/preview_editor.cpp
@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2020  Igara Studio S.A.
+// Copyright (C) 2018-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -33,6 +33,7 @@
 #include "ui/base.h"
 #include "ui/button.h"
 #include "ui/close_event.h"
+#include "ui/fit_bounds.h"
 #include "ui/message.h"
 #include "ui/system.h"
 
@@ -219,25 +220,27 @@ bool PreviewEditorWindow::onProcessMessage(ui::Message* msg)
 {
   switch (msg->type()) {
 
-    case kOpenMessage:
-      {
-        SkinTheme* theme = SkinTheme::instance();
-
-        // Default bounds
-        gfx::Size desktopSize = ui::get_desktop_size();
-        const int width = desktopSize.w/4;
-        const int height = desktopSize.h/4;
-        int extra = 2*theme->dimensions.miniScrollbarSize();
-        setBounds(
-          gfx::Rect(
-            desktopSize.w - width - ToolBar::instance()->bounds().w - extra,
-            desktopSize.h - height - StatusBar::instance()->bounds().h - extra,
-            width, height));
-
-        load_window_pos(this, "MiniEditor", false);
-        invalidate();
+    case kOpenMessage: {
+      Manager* manager = this->manager();
+      Display* mainDisplay = manager->display();
+
+      gfx::Rect defaultBounds(mainDisplay->size() / 4);
+      SkinTheme* theme = SkinTheme::instance();
+      gfx::Rect mainWindow = manager->bounds();
+
+      int extra = theme->dimensions.miniScrollbarSize();
+      if (get_multiple_displays()) {
+        extra *= mainDisplay->scale();
       }
+      defaultBounds.x = mainWindow.x2() - ToolBar::instance()->sizeHint().w - defaultBounds.w - extra;
+      defaultBounds.y = mainWindow.y2() - StatusBar::instance()->sizeHint().h - defaultBounds.h - extra;
+
+      fit_bounds(mainDisplay, this, defaultBounds);
+
+      load_window_pos(this, "MiniEditor", false);
+      invalidate();
       break;
+    }
 
     case kCloseMessage:
       save_window_pos(this, "MiniEditor");
diff --git a/src/app/ui/status_bar.cpp b/src/app/ui/status_bar.cpp
index 7e4745af5f..76c09803c9 100644
--- a/src/app/ui/status_bar.cpp
+++ b/src/app/ui/status_bar.cpp
@@ -878,6 +878,8 @@ void StatusBar::showSnapToGridWarning(bool state)
     if (!m_snapToGridWindow)
       m_snapToGridWindow = new SnapToGridWindow;
 
+    m_snapToGridWindow->setDisplay(display(), false);
+
     if (!m_snapToGridWindow->isVisible()) {
       m_snapToGridWindow->openWindow();
       m_snapToGridWindow->remapWindow();
diff --git a/src/app/ui/timeline/timeline.cpp b/src/app/ui/timeline/timeline.cpp
index cafed4de3e..3cb06bda16 100644
--- a/src/app/ui/timeline/timeline.cpp
+++ b/src/app/ui/timeline/timeline.cpp
@@ -1243,12 +1243,12 @@ bool Timeline::onProcessMessage(Message* msg)
             if (!m_confPopup->isVisible()) {
               gfx::Rect bounds = m_confPopup->bounds();
               ui::fit_bounds(display(), BOTTOM, gearBounds, bounds);
-
-              m_confPopup->moveWindow(bounds);
+              ui::fit_bounds(display(), m_confPopup, bounds);
               m_confPopup->openWindow();
             }
-            else
-              m_confPopup->closeWindow(NULL);
+            else {
+              m_confPopup->closeWindow(nullptr);
+            }
             break;
           }
 
@@ -1258,7 +1258,7 @@ bool Timeline::onProcessMessage(Message* msg)
               if (m_clk.frame == m_hot.frame) {
                 Menu* popupMenu = AppMenus::instance()->getFramePopupMenu();
                 if (popupMenu) {
-                  popupMenu->showPopup(mouseMsg->position());
+                  popupMenu->showPopup(mouseMsg->position(), display());
 
                   m_state = STATE_STANDBY;
                   invalidate();
@@ -1273,7 +1273,7 @@ bool Timeline::onProcessMessage(Message* msg)
               if (m_clk.layer == m_hot.layer) {
                 Menu* popupMenu = AppMenus::instance()->getLayerPopupMenu();
                 if (popupMenu) {
-                  popupMenu->showPopup(mouseMsg->position());
+                  popupMenu->showPopup(mouseMsg->position(), display());
 
                   m_state = STATE_STANDBY;
                   invalidate();
@@ -1293,7 +1293,7 @@ bool Timeline::onProcessMessage(Message* msg)
                   AppMenus::instance()->getCelMovementPopupMenu():
                   AppMenus::instance()->getCelPopupMenu();
               if (popupMenu) {
-                popupMenu->showPopup(mouseMsg->position());
+                popupMenu->showPopup(mouseMsg->position(), display());
 
                 // Do not drop in this function, the drop is done from
                 // the menu in case we've used the
@@ -1321,7 +1321,7 @@ bool Timeline::onProcessMessage(Message* msg)
                 Menu* popupMenu = AppMenus::instance()->getTagPopupMenu();
                 if (popupMenu) {
                   AppMenuItem::setContextParams(params);
-                  popupMenu->showPopup(mouseMsg->position());
+                  popupMenu->showPopup(mouseMsg->position(), display());
                   AppMenuItem::setContextParams(Params());
 
                   m_state = STATE_STANDBY;
diff --git a/src/ui/combobox.cpp b/src/ui/combobox.cpp
index cf8f944b22..7e19c7c405 100644
--- a/src/ui/combobox.cpp
+++ b/src/ui/combobox.cpp
@@ -376,7 +376,7 @@ bool ComboBox::onProcessMessage(Message* msg)
 
           MouseMessage* mouseMsg = static_cast<MouseMessage*>(msg);
           Widget* pick = manager()->pickFromScreenPos(
-            display()->nativeWindow()->pointFromScreen(mouseMsg->position()));
+            mouseMsg->display()->nativeWindow()->pointFromScreen(mouseMsg->position()));
           if (pick && pick->hasAncestor(this))
             return true;
         }
diff --git a/src/ui/display.h b/src/ui/display.h
index cad5c99865..544411f5d5 100644
--- a/src/ui/display.h
+++ b/src/ui/display.h
@@ -33,6 +33,7 @@ namespace ui {
     os::Window* nativeWindow() { return m_nativeWindow.get(); }
     os::Surface* surface() const;
 
+    int scale() const { return m_nativeWindow->scale(); }
     gfx::Size size() const;
     gfx::Rect bounds() const { return gfx::Rect(size()); }
 
diff --git a/src/ui/entry.cpp b/src/ui/entry.cpp
index b78f2ec8eb..90b82a5fba 100644
--- a/src/ui/entry.cpp
+++ b/src/ui/entry.cpp
@@ -819,7 +819,7 @@ void Entry::showEditPopupMenu(const gfx::Point& pt)
     paste.setEnabled(false);
   }
 
-  menu.showPopup(pt);
+  menu.showPopup(pt, display());
 }
 
 class Entry::CalcBoxesTextDelegate : public os::DrawTextDelegate {
diff --git a/src/ui/fit_bounds.cpp b/src/ui/fit_bounds.cpp
index ec8f059222..339cd4047f 100644
--- a/src/ui/fit_bounds.cpp
+++ b/src/ui/fit_bounds.cpp
@@ -1,5 +1,5 @@
 // Aseprite UI Library
-// Copyright (C) 2019-2020  Igara Studio S.A.
+// Copyright (C) 2019-2021  Igara Studio S.A.
 // Copyright (C) 2001-2016  David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -16,6 +16,7 @@
 #include "ui/base.h"
 #include "ui/display.h"
 #include "ui/system.h"
+#include "ui/window.h"
 
 namespace ui {
 
@@ -87,4 +88,50 @@ int fit_bounds(Display* display, int arrowAlign, const gfx::Rect& target, gfx::R
   return arrowAlign;
 }
 
+void fit_bounds(Display* parentDisplay,
+                Window* window,
+                const gfx::Rect& candidateBoundsRelativeToParentDisplay,
+                std::function<void(const gfx::Rect& workarea,
+                                   gfx::Rect& bounds,
+                                   std::function<gfx::Rect(Widget*)> getWidgetBounds)> fitLogic)
+{
+  gfx::Point pos = candidateBoundsRelativeToParentDisplay.origin();
+
+  if (get_multiple_displays() && window->shouldCreateNativeWindow()) {
+    const os::Window* nativeWindow = parentDisplay->nativeWindow();
+    const gfx::Rect workarea = nativeWindow->screen()->workarea();
+    const int scale = nativeWindow->scale();
+
+    // Screen frame bounds
+    gfx::Rect frame(
+      nativeWindow->pointToScreen(pos),
+      candidateBoundsRelativeToParentDisplay.size() * scale);
+
+    if (fitLogic)
+      fitLogic(workarea, frame, [](Widget* widget){ return widget->boundsOnScreen(); });
+
+    frame.x = base::clamp(frame.x, workarea.x, workarea.x2() - frame.w);
+    frame.y = base::clamp(frame.y, workarea.y, workarea.y2() - frame.h);
+
+    // Set frame bounds directly
+    window->setBounds(gfx::Rect(0, 0, frame.w / scale, frame.h / scale));
+    window->loadNativeFrame(frame);
+
+    if (window->isVisible())
+      window->expandWindow(frame.size() / scale);
+  }
+  else {
+    const gfx::Rect displayBounds(parentDisplay->size());
+    gfx::Rect frame(candidateBoundsRelativeToParentDisplay);
+
+    if (fitLogic)
+      fitLogic(displayBounds, frame, [](Widget* widget){ return widget->bounds(); });
+
+    frame.x = base::clamp(frame.x, 0, displayBounds.w - frame.w);
+    frame.y = base::clamp(frame.y, 0, displayBounds.h - frame.h);
+
+    window->setBounds(frame);
+  }
+}
+
 } // namespace ui
diff --git a/src/ui/fit_bounds.h b/src/ui/fit_bounds.h
index f6d1451f67..a7bf4a586d 100644
--- a/src/ui/fit_bounds.h
+++ b/src/ui/fit_bounds.h
@@ -1,5 +1,5 @@
 // Aseprite UI Library
-// Copyright (C) 2019  Igara Studio S.A.
+// Copyright (C) 2019-2021  Igara Studio S.A.
 // Copyright (C) 2016  David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -11,12 +11,32 @@
 
 #include "gfx/fwd.h"
 
+#include <functional>
+
 namespace ui {
 
   class Display;
+  class Widget;
+  class Window;
 
   int fit_bounds(Display* display, int arrowAlign, const gfx::Rect& target, gfx::Rect& bounds);
 
+  // Fits a possible rectangle for the given window fitting it with a
+  // special logic. It works for both cases:
+  // 1. With multiple windows (so the limit is the parentDisplay screen workarea)
+  // 2. Or with one window (so the limit is the just display area)
+  //
+  // The getWidgetBounds() can be used to get other widgets positions
+  // in the "fitLogic" (the bounds will be relative to the screen or
+  // to the display depending if get_multiple_displays() is true or
+  // false).
+  void fit_bounds(Display* parentDisplay,
+                  Window* window,
+                  const gfx::Rect& candidateBoundsRelativeToParentDisplay,
+                  std::function<void(const gfx::Rect& workarea,
+                                     gfx::Rect& bounds,
+                                     std::function<gfx::Rect(Widget*)> getWidgetBounds)> fitLogic = nullptr);
+
 } // namespace ui
 
 #endif
diff --git a/src/ui/int_entry.cpp b/src/ui/int_entry.cpp
index 9d7d8e77e7..224c4002ba 100644
--- a/src/ui/int_entry.cpp
+++ b/src/ui/int_entry.cpp
@@ -16,6 +16,7 @@
 #include "gfx/rect.h"
 #include "gfx/region.h"
 #include "os/font.h"
+#include "ui/fit_bounds.h"
 #include "ui/manager.h"
 #include "ui/message.h"
 #include "ui/popup_window.h"
@@ -182,20 +183,28 @@ void IntEntry::openPopup()
   m_popupWindow->addChild(&m_slider);
   m_popupWindow->Close.connect(&IntEntry::onPopupClose, this);
 
-  Rect rc = bounds();
-  gfx::Size sz = m_popupWindow->sizeHint();
-  gfx::Size displaySize = display()->size();
-  rc.w = 128*guiscale();
-  if (rc.x+rc.w > displaySize.w)
-    rc.x = rc.x-rc.w+bounds().w;
-  if (rc.y+rc.h+sz.h < displaySize.h)
-    rc.y += rc.h;
-  else
-    rc.y -= sz.h;
-  m_popupWindow->setBounds(rc);
-
-  Region rgn(rc.createUnion(bounds()));
-  rgn.createUnion(rgn, Region(bounds()));
+  fit_bounds(
+    display(),
+    m_popupWindow,
+    gfx::Rect(0, 0, 128*guiscale(), m_popupWindow->sizeHint().h),
+    [this](const gfx::Rect& workarea,
+           gfx::Rect& rc,
+           std::function<gfx::Rect(Widget*)> getWidgetBounds) {
+      Rect entryBounds = getWidgetBounds(this);
+
+      rc.x = entryBounds.x;
+      rc.y = entryBounds.y2();
+
+      if (rc.x2() > workarea.x2())
+        rc.x = rc.x-rc.w+entryBounds.w;
+
+      if (rc.y2() > workarea.y2())
+        rc.y = entryBounds.y-entryBounds.h;
+
+      m_popupWindow->setBounds(rc);
+    });
+
+  Region rgn(m_popupWindow->boundsOnScreen().createUnion(boundsOnScreen()));
   m_popupWindow->setHotRegion(rgn);
 
   m_popupWindow->openWindow();
diff --git a/src/ui/manager.cpp b/src/ui/manager.cpp
index b2b33a9360..1ef5dc1ea8 100644
--- a/src/ui/manager.cpp
+++ b/src/ui/manager.cpp
@@ -24,6 +24,7 @@
 #include "base/time.h"
 #include "os/event.h"
 #include "os/event_queue.h"
+#include "os/screen.h"
 #include "os/surface.h"
 #include "os/system.h"
 #include "os/window.h"
@@ -1132,6 +1133,21 @@ void Manager::removeMessagesForTimer(Timer* timer)
   }
 }
 
+void Manager::removeMessagesForDisplay(Display* display)
+{
+#ifdef DEBUG_UI_THREADS
+  ASSERT(manager_thread == base::this_thread::native_id());
+#endif
+
+  for (Message* msg : msg_queue)
+    if (msg->display() == display)
+      msg->removeRecipient(msg->recipient());
+
+  for (Message* msg : used_msg_queue)
+    if (msg->display() == display)
+      msg->removeRecipient(msg->recipient());
+}
+
 void Manager::removePaintMessagesForDisplay(Display* display)
 {
 #ifdef DEBUG_UI_THREADS
@@ -1141,7 +1157,7 @@ void Manager::removePaintMessagesForDisplay(Display* display)
   for (auto it=msg_queue.begin(); it != msg_queue.end(); ) {
     Message* msg = *it;
     if (msg->type() == kPaintMessage &&
-        static_cast<PaintMessage*>(msg)->display() == display) {
+        msg->display() == display) {
       delete msg;
       it = msg_queue.erase(it);
     }
@@ -1269,22 +1285,18 @@ void Manager::_openWindow(Window* window, bool center)
 
   // Relayout
   if (center)
-    window->centerWindow();
+    window->centerWindow(parentDisplay);
   else
     window->layout();
 
   // If the window already was set a display, we don't setup it
   // (i.e. in the case of combobox popup/window the display field is
   // set to the same display where the ComboBox widget is located)
-  if (window->display() == &m_display) {
+  if (!window->hasDisplaySet()) {
     // In other case, we can try to create a display/native window for
     // the UI window.
     if (get_multiple_displays()
-        && !window->isDesktop()
-#if 1   // TODO Add support for menuboxes and tooltips with native windows
-        && window->isSizeable()
-#endif
-        ) {
+        && window->shouldCreateNativeWindow()) {
       const int scale = parentDisplay->nativeWindow()->scale();
 
       os::WindowSpec spec;
@@ -1298,6 +1310,31 @@ void Manager::_openWindow(Window* window, bool center)
         frame *= scale;
         frame.offset(relativeToFrame.origin());
       }
+
+      // Limit window position using the union of all workareas
+      //
+      // TODO at least the title bar should be visible so we can
+      //      resize it, because workareas can form an irregular shape
+      //      (not rectangular) the calculation is a little more
+      //      complex
+      {
+        gfx::Region wa;
+        os::ScreenList screens;
+        os::instance()->listScreens(screens);
+        for (const auto& screen : screens)
+          wa |= gfx::Region(screen->workarea());
+
+        // TODO use a "visibleFrameRegion = frame & wa" to check the
+        // visible regions and calculate if we should move the frame
+        // position
+
+        gfx::Rect waBounds = wa.bounds();
+        if (frame.x < waBounds.x) frame.x = waBounds.x;
+        if (frame.y < waBounds.y) frame.y = waBounds.y;
+        if (frame.x2() > waBounds.x2()) frame.w -= frame.x2() - waBounds.x2();
+        if (frame.y2() > waBounds.y2()) frame.h -= frame.y2() - waBounds.y2();
+      }
+
       spec.position(os::WindowSpec::Position::Frame);
       spec.frame(frame);
       spec.scale(scale);
@@ -1374,8 +1411,8 @@ void Manager::_closeWindow(Window* window, bool redraw_background)
     ASSERT(windowDisplay);
     ASSERT(windowDisplay != this->display());
 
-    // Remove all paint messages for this display.
-    removePaintMessagesForDisplay(windowDisplay);
+    // Remove all messages for this display.
+    removeMessagesForDisplay(windowDisplay);
 
     window->setDisplay(nullptr, false);
     windowDisplay->nativeWindow()->setUserData<void*>(nullptr);
diff --git a/src/ui/manager.h b/src/ui/manager.h
index 00b91973cb..3ab29d82dc 100644
--- a/src/ui/manager.h
+++ b/src/ui/manager.h
@@ -80,6 +80,7 @@ namespace ui {
     void removeMessagesFor(Widget* widget);
     void removeMessagesFor(Widget* widget, MessageType type);
     void removeMessagesForTimer(Timer* timer);
+    void removeMessagesForDisplay(Display* display);
     void removePaintMessagesForDisplay(Display* display);
 
     void addMessageFilter(int message, Widget* widget);
diff --git a/src/ui/menu.cpp b/src/ui/menu.cpp
index 8e45da1cbf..e13ff97eb9 100644
--- a/src/ui/menu.cpp
+++ b/src/ui/menu.cpp
@@ -292,7 +292,8 @@ bool MenuItem::hasSubmenu() const
   return (m_submenu && !m_submenu->children().empty());
 }
 
-void Menu::showPopup(const gfx::Point& pos)
+void Menu::showPopup(const gfx::Point& pos,
+                     Display* parentDisplay)
 {
   // Generally, when we call showPopup() the menu shouldn't contain a
   // parent menu-box, because we're filtering kMouseDownMessage to
@@ -322,11 +323,9 @@ void Menu::showPopup(const gfx::Point& pos)
 
   window->remapWindow();
 
-  // Menubox position
-  gfx::Size displaySize = display()->size();
-  window->positionWindow(
-    base::clamp(pos.x, 0, displaySize.w - window->bounds().w),
-    base::clamp(pos.y, 0, displaySize.h - window->bounds().h));
+  fit_bounds(parentDisplay,
+             window.get(),
+             gfx::Rect(pos, window->size()));
 
   add_scrollbars_if_needed(window.get());
 
@@ -442,20 +441,20 @@ bool MenuBox::onProcessMessage(Message* msg)
 
     case kMouseDownMessage:
     case kDoubleClickMessage:
-      if (menu) {
+      if (menu && msg->display()) {
         ASSERT(menu->parent() == this);
 
         if (get_base(this)->is_processing)
           break;
 
-        gfx::Point mousePos = static_cast<MouseMessage*>(msg)->position();
+        const gfx::Point mousePos = static_cast<MouseMessage*>(msg)->position();
+        const gfx::Point screenPos = msg->display()->nativeWindow()->pointToScreen(mousePos);
 
         // Here we catch the filtered messages (menu-bar or the
         // popuped menu-box) to detect if the user press outside of
         // the widget
         if (msg->type() == kMouseDownMessage && m_base != nullptr) {
-          Widget* picked = manager()->pickFromScreenPos(
-            display()->nativeWindow()->pointToScreen(mousePos));
+          Widget* picked = manager()->pickFromScreenPos(screenPos);
 
           // If one of these conditions are accomplished we have to
           // close all menus (back to menu-bar or close the popuped
@@ -466,16 +465,17 @@ bool MenuBox::onProcessMessage(Message* msg)
               (get_base_menubox(picked) != this ||
                (this->type() == kMenuBarWidget &&
                 picked->type() == kMenuWidget))) {
-
             // The user click outside all the menu-box/menu-items, close all
             menu->closeAll();
+
+            // Change to "return false" if you want to send the click
+            // to the window after closing all menus.
             return true;
           }
         }
 
         // Get the widget below the mouse cursor
-        Widget* picked = menu->pick(mousePos);
-        if (picked) {
+        if (Widget* picked = menu->pickFromScreenPos(screenPos)) {
           if ((picked->type() == kMenuItemWidget) &&
               !(picked->hasFlags(DISABLED))) {
             MenuItem* pickedItem = static_cast<MenuItem*>(picked);
@@ -814,9 +814,6 @@ bool MenuItem::onProcessMessage(Message* msg)
         ASSERT(base->is_processing);
         ASSERT(hasSubmenu());
 
-        Rect old_pos = window()->bounds();
-        old_pos.w -= 1*guiscale();
-
         MenuBox* menubox = new MenuBox();
         m_submenu_menubox = menubox;
         menubox->setMenu(m_submenu);
@@ -824,42 +821,47 @@ bool MenuItem::onProcessMessage(Message* msg)
         // New window and new menu-box
         auto window = new MenuBoxWindow(menubox);
 
-        // Menubox position
-        Rect pos = window->bounds();
-        Size displaySize = display()->size();
-
-        if (inBar()) {
-          pos.x = base::clamp(bounds().x, 0, displaySize.w-pos.w);
-          pos.y = std::max(0, bounds().y2());
-        }
-        else {
-          int x_left = old_pos.x - pos.w;
-          int x_right = old_pos.x2();
-          int x, y = bounds().y-3*guiscale();
-          Rect r1(0, 0, pos.w, pos.h), r2(0, 0, pos.w, pos.h);
-
-          r1.x = x_left = base::clamp(x_left, 0, displaySize.w-pos.w);
-          r2.x = x_right = base::clamp(x_right, 0, displaySize.w-pos.w);
-          r1.y = r2.y = y = base::clamp(y, 0, displaySize.h-pos.h);
-
-          // Calculate both intersections
-          gfx::Rect s1 = r1.createIntersection(old_pos);
-          gfx::Rect s2 = r2.createIntersection(old_pos);
-
-          if (s2.isEmpty())
-            x = x_right;        // Use the right because there aren't intersection with it
-          else if (s1.isEmpty())
-            x = x_left;         // Use the left because there are not intersection
-          else if (r2.w*r2.h <= r1.w*r1.h)
-            x = x_right;                // Use the right because there are less intersection area
-          else
-            x = x_left;         // Use the left because there are less intersection area
-
-          pos.x = x;
-          pos.y = y;
-        }
+        fit_bounds(
+          display(), window, window->bounds(),
+          [this](const gfx::Rect& workarea,
+                 gfx::Rect& pos,
+                 std::function<gfx::Rect(Widget*)> getWidgetBounds){
+            Rect parentPos = getWidgetBounds(this->window());
+            Rect bounds = getWidgetBounds(this);
+
+            if (inBar()) {
+              pos.x = base::clamp(bounds.x, workarea.x, workarea.x2()-pos.w);
+              pos.y = std::max(workarea.y, bounds.y2());
+            }
+            else {
+              int x_left = parentPos.x - pos.w + 1*guiscale();
+              int x_right = parentPos.x2() - 1*guiscale();
+              int x, y = bounds.y-3*guiscale();
+              Rect r1(0, 0, pos.w, pos.h);
+              Rect r2(0, 0, pos.w, pos.h);
+
+              r1.x = x_left = base::clamp(x_left, 0, workarea.w-pos.w);
+              r2.x = x_right = base::clamp(x_right, 0, workarea.w-pos.w);
+              r1.y = r2.y = y = base::clamp(y, 0, workarea.h-pos.h);
+
+              // Calculate both intersections
+              const gfx::Rect s1 = r1.createIntersection(parentPos);
+              const gfx::Rect s2 = r2.createIntersection(parentPos);
+
+              if (s2.isEmpty())
+                x = x_right;        // Use the right because there aren't intersection with it
+              else if (s1.isEmpty())
+                x = x_left;         // Use the left because there are not intersection
+              else if (s2.w*s2.h <= s1.w*s1.h)
+                x = x_right;        // Use the right because there are less intersection area
+              else
+                x = x_left;         // Use the left because there are less intersection area
+
+              pos.x = x;
+              pos.y = y;
+            }
+          });
 
-        window->positionWindow(pos.x, pos.y);
         add_scrollbars_if_needed(window);
 
         // Set the focus to the new menubox
@@ -1133,7 +1135,7 @@ void Menu::unhighlightItem()
   highlightItem(nullptr, false, false, false);
 }
 
-bool MenuItem::inBar()
+bool MenuItem::inBar() const
 {
   return
     (parent() &&
diff --git a/src/ui/menu.h b/src/ui/menu.h
index 432393463a..e641d47d9a 100644
--- a/src/ui/menu.h
+++ b/src/ui/menu.h
@@ -1,5 +1,5 @@
 // Aseprite UI Library
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -28,7 +28,8 @@ namespace ui {
     Menu();
     ~Menu();
 
-    void showPopup(const gfx::Point& pos);
+    void showPopup(const gfx::Point& pos,
+                   Display* parentDisplay);
     Widget* findItemById(const char* id);
 
     // Returns the MenuItem that has as submenu this menu.
@@ -141,7 +142,7 @@ namespace ui {
     virtual void onClick();
     virtual void onValidate();
 
-    bool inBar();
+    bool inBar() const;
 
   private:
     void openSubmenu(bool select_first);
diff --git a/src/ui/popup_window.cpp b/src/ui/popup_window.cpp
index dbf53c9dbe..68412ea8cd 100644
--- a/src/ui/popup_window.cpp
+++ b/src/ui/popup_window.cpp
@@ -1,5 +1,5 @@
 // Aseprite UI Library
-// Copyright (C) 2020  Igara Studio S.A.
+// Copyright (C) 2020-2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -27,8 +27,6 @@ PopupWindow::PopupWindow(const std::string& text,
   : Window(text.empty() ? WithoutTitleBar: WithTitleBar, text)
   , m_clickBehavior(clickBehavior)
   , m_enterBehavior(enterBehavior)
-  , m_filtering(false)
-  , m_fixed(false)
 {
   setSizeable(false);
   setMoveable(false);
@@ -53,11 +51,11 @@ PopupWindow::~PopupWindow()
   stopFilteringMessages();
 }
 
-void PopupWindow::setHotRegion(const gfx::Region& region)
+void PopupWindow::setHotRegion(const gfx::Region& screenRegion)
 {
   startFilteringMessages();
 
-  m_hotRegion = region;
+  m_hotRegion = screenRegion;
 }
 
 void PopupWindow::setClickBehavior(ClickBehavior behavior)
@@ -137,26 +135,30 @@ bool PopupWindow::onProcessMessage(Message* msg)
 
     case kMouseDownMessage:
       if (m_filtering &&
-          manager()->getTopWindow() == this) {
+          manager()->getTopWindow() == this &&
+          msg->display()) {
         gfx::Point mousePos = static_cast<MouseMessage*>(msg)->position();
+        gfx::Point screenPos = msg->display()->nativeWindow()->pointToScreen(mousePos);
 
         switch (m_clickBehavior) {
 
           // If the user click outside the window, we have to close
           // the tooltip window.
           case ClickBehavior::CloseOnClickInOtherWindow: {
-            Widget* picked = pick(mousePos);
+            Widget* picked = pickFromScreenPos(screenPos);
             if (!picked || picked->window() != this) {
               closeWindow(nullptr);
             }
             break;
           }
 
-          case ClickBehavior::CloseOnClickOutsideHotRegion:
-            if (!m_hotRegion.contains(mousePos)) {
+          case ClickBehavior::CloseOnClickOutsideHotRegion: {
+            // Convert the mousePos from display() coordinates to screen
+            if (!m_hotRegion.contains(screenPos)) {
               closeWindow(nullptr);
             }
             break;
+          }
         }
       }
       break;
@@ -164,12 +166,14 @@ bool PopupWindow::onProcessMessage(Message* msg)
     case kMouseMoveMessage:
       if (m_fixed &&
           !m_hotRegion.isEmpty() &&
-          manager()->getCapture() == nullptr) {
+          manager()->getCapture() == nullptr &&
+          msg->display()) {
         gfx::Point mousePos = static_cast<MouseMessage*>(msg)->position();
+        gfx::Point screenPos = msg->display()->nativeWindow()->pointToScreen(mousePos);
 
         // If the mouse is outside the hot-region we have to close the
         // window.
-        if (!m_hotRegion.contains(mousePos))
+        if (!m_hotRegion.contains(screenPos))
           closeWindow(nullptr);
       }
       break;
diff --git a/src/ui/popup_window.h b/src/ui/popup_window.h
index a97f0d04ab..469b32a871 100644
--- a/src/ui/popup_window.h
+++ b/src/ui/popup_window.h
@@ -1,4 +1,5 @@
 // Aseprite UI Library
+// Copyright (C) 2021  Igara Studio S.A.
 // Copyright (C) 2001-2017  David Capello
 //
 // This file is released under the terms of the MIT license.
@@ -33,7 +34,10 @@ namespace ui {
 
     // Sets the hot region. This region indicates the area where the
     // mouse can be located and the window will be kept open.
-    void setHotRegion(const gfx::Region& region);
+    //
+    // The screenRegion must be specified in native screen coordinates.
+    void setHotRegion(const gfx::Region& screenRegion);
+
     void setClickBehavior(ClickBehavior behavior);
     void setEnterBehavior(EnterBehavior behavior);
 
@@ -54,8 +58,8 @@ namespace ui {
     ClickBehavior m_clickBehavior;
     EnterBehavior m_enterBehavior;
     gfx::Region m_hotRegion;
-    bool m_filtering;
-    bool m_fixed;
+    bool m_filtering = false;
+    bool m_fixed = false;
   };
 
   class TransparentPopupWindow : public PopupWindow {
diff --git a/src/ui/widget.cpp b/src/ui/widget.cpp
index 1fc599f68c..2c5e567127 100644
--- a/src/ui/widget.cpp
+++ b/src/ui/widget.cpp
@@ -698,6 +698,16 @@ Rect Widget::clientChildrenBounds() const
               m_bounds.h - border().height());
 }
 
+gfx::Rect Widget::boundsOnScreen() const
+{
+  gfx::Rect rc = bounds();
+  os::Window* nativeWindow = display()->nativeWindow();
+  rc = gfx::Rect(
+    nativeWindow->pointToScreen(rc.origin()),
+    nativeWindow->pointToScreen(rc.point2()));
+  return rc;
+}
+
 void Widget::setBounds(const Rect& rc)
 {
   ResizeEvent ev(this, rc);
diff --git a/src/ui/widget.h b/src/ui/widget.h
index d934d4b5dc..791a65ca22 100644
--- a/src/ui/widget.h
+++ b/src/ui/widget.h
@@ -242,6 +242,9 @@ namespace ui {
     gfx::Rect childrenBounds() const;
     gfx::Rect clientChildrenBounds() const;
 
+    // Bounds of this widget or window on native screen/desktop coordinates.
+    gfx::Rect boundsOnScreen() const;
+
     // Sets the bounds of the widget generating a onResize() event.
     void setBounds(const gfx::Rect& rc);
 
diff --git a/src/ui/window.cpp b/src/ui/window.cpp
index 4668fe0c07..635da749b7 100644
--- a/src/ui/window.cpp
+++ b/src/ui/window.cpp
@@ -309,19 +309,24 @@ void Window::remapWindow()
   invalidate();
 }
 
-void Window::centerWindow()
+void Window::centerWindow(Display* parentDisplay)
 {
-  Widget* manager = this->manager();
-
   if (m_isAutoRemap)
     remapWindow();
 
-  positionWindow(manager->bounds().w/2 - bounds().w/2,
-                 manager->bounds().h/2 - bounds().h/2);
+  if (!parentDisplay)
+    parentDisplay = manager()->getDefault()->display();
+
+  gfx::Size displaySize = parentDisplay->size();
+  positionWindow(displaySize.w/2 - bounds().w/2,
+                 displaySize.h/2 - bounds().h/2);
 }
 
 void Window::positionWindow(int x, int y)
 {
+  // TODO don't use in ownDisplay() windows
+  ASSERT(!ownDisplay());
+
   if (m_isAutoRemap)
     remapWindow();
 
@@ -437,6 +442,12 @@ bool Window::onProcessMessage(Message* msg)
           }
           if (action != os::WindowAction::Cancel) {
             display()->nativeWindow()->performWindowAction(action, nullptr);
+
+            // As Window::moveWindow() will not be called, we have to
+            // call onWindowMovement() event from here.
+            if (action == os::WindowAction::Move)
+              onWindowMovement();
+
             return true;
           }
         }
diff --git a/src/ui/window.h b/src/ui/window.h
index e2db276b66..38066f03f7 100644
--- a/src/ui/window.h
+++ b/src/ui/window.h
@@ -31,6 +31,7 @@ namespace ui {
     bool ownDisplay() const { return m_ownDisplay; }
     Display* display() const;
     void setDisplay(Display* display, const bool own);
+    bool hasDisplaySet() const { return m_display != nullptr; }
 
     Widget* closer() const { return m_closer; }
 
@@ -41,7 +42,7 @@ namespace ui {
     void setWantFocus(bool state);
 
     void remapWindow();
-    void centerWindow();
+    void centerWindow(Display* parentDisplay = nullptr);
     void positionWindow(int x, int y);
     void moveWindow(const gfx::Rect& rect);
 
@@ -60,6 +61,11 @@ namespace ui {
     bool isSizeable() const { return m_isSizeable; }
     bool isMoveable() const { return m_isMoveable; }
 
+    bool shouldCreateNativeWindow() const {
+      return (!isDesktop() &&
+              !isTransparent());
+    }
+
     HitTest hitTest(const gfx::Point& point);
 
     // Last native window frame bounds. Saved just before we close the