Fix multiple issues with native selection mode in Browse mode, includ…

…ing:

* In firefox, If NVDA fails to update the native selection when turning on native selection mode, it is now left off, and the user is notified that native selection mode is not supported. this stops errors when moving with the arrow keys in Thunderbird after turning on native selection mode.
* Exceptions are logged when turning on and off native selection mode.
* If native selection mode is not supported when trying to turn it on, NVDA honors the _nativeAppSelectionMode boolean to tailor the message to state that it cannot be turned off, if it is on (though not supported).
* UIA browse mode documents (E.g. MS word) set _nativeSelectionMode to True, though it cannot be turned off. This not only provides a better message to the user if they try and toggle it, but it also has the advantage that copying with control+c from MS word browse mode, will now also copy with formatting.

source/NVDAObjects/UIA/web.py

@@ -487,6 +487,7 @@ def HeadingControlQuicknavIterator(itemType, document, position, direction="next
 
 class UIAWebTreeInterceptor(cursorManager.ReviewCursorManager, UIABrowseModeDocument):
 	TextInfo = UIABrowseModeDocumentTextInfo
+	_nativeAppSelectionMode = False
 
 	def makeTextInfo(self, position):
 		try:

source/NVDAObjects/UIA/wordDocument.py

@@ -554,6 +554,12 @@ def event_UIA_notification(self, activityId=None, **kwargs):
 		# such as "delete back word" when Control+Backspace is pressed.
 		if activityId == "AccSN2":  # Delete activity ID
 			return
+		# copy to clipboard
+		if activityId == 'AccSN3':
+			ti = self.treeInterceptor
+			if ti and not ti.passThrough:
+				# Browse mode provides its own copy to clipboard message.
+				return
 		super(WordDocument, self).event_UIA_notification(**kwargs)
 
 	# The following overide of the EditableText._caretMoveBySentenceHelper private method

source/UIAHandler/browseMode.py

@@ -373,6 +373,7 @@ class UIABrowseModeDocument(UIADocumentWithTableNavigation,browseMode.BrowseMode
 	# UIA browseMode documents cannot remember caret positions across loads (I.e. when going back a page in Edge) 
 	# Because UIA TextRanges are opaque and are tied specifically to one particular document.
 	shouldRememberCaretPositionAcrossLoads=False
+	_nativeAppSelectionMode = True
 
 	def event_UIA_activeTextPositionChanged(self, obj, nextHandler, textRange=None):
 		if not self.isReady:

source/browseMode.py

@@ -2036,21 +2036,30 @@ def clearAppSelection(self):
 	)
 	def script_toggleNativeAppSelectionMode(self, gesture: inputCore.InputGesture):
 		if not self._nativeAppSelectionModeSupported:
-			# Translators: the message when native selection mode is not available in this browse mode document.
-			ui.message(_("Native selection mode unsupported in this document"))
+			if not self._nativeAppSelectionMode:
+				# Translators: the message when native selection mode is not available in this browse mode document.
+				ui.message(_("Native selection mode unsupported in this browse mode document"))
+			else:
+				# Translators: the message when native selection mode is not available in this browse mode document.
+				ui.message(_("Native selection mode cannot be turned off in this browse mode document"))
 			return
-		self._nativeAppSelectionMode = not self._nativeAppSelectionMode
-		if self._nativeAppSelectionMode:
-			# Translators: reported when native selection mode is toggled on.
-			ui.message(_("Native app selection mode enabled."))
+		nativeAppSelectionModeOn = not self._nativeAppSelectionMode
+		if nativeAppSelectionModeOn:
 			try:
 				self.updateAppSelection()
 			except NotImplementedError:
-				pass
+				log.debugWarning("updateAppSelection failed", exc_info=True)
+				# Translators: the message when native selection mode is not available in this browse mode document.
+				ui.message(_("Native selection mode unsupported in this document"))
+				return
+			self._nativeAppSelectionMode = True
+			# Translators: reported when native selection mode is toggled on.
+			ui.message(_("Native app selection mode enabled"))
 		else:
-			# Translators: reported when native selection mode is toggled off.
-			ui.message(_("Native app selection mode disabled."))
 			try:
 				self.clearAppSelection()
-			except NotImplementedError:
-				pass
+			except (NotImplementedError, COMError):
+				log.debugWarning("clearAppSelection failed", exc_info=True)
+			self._nativeAppSelectionMode = False
+			# Translators: reported when native selection mode is toggled off.
+			ui.message(_("Native app selection mode disabled"))

source/virtualBuffers/gecko_ia2.py

@@ -699,22 +699,26 @@ def updateAppSelection(self):
 		except COMError as e:
 			raise NotImplementedError from e
 		selInfo = self.makeTextInfo(textInfos.POSITION_SELECTION)
-		selFields = selInfo.getTextWithFields()
-		ia2Sel = _Ia2Selection()
-
-		log.debug("checking fields...")
-		self._getStartSelection(ia2Sel, selFields)
-		self._getEndSelection(ia2Sel, selFields)
-
-		log.debug("setting selection...")
-		r = IA2TextSelection(
-			ia2Sel.startObj,
-			ia2Sel.startOffset,
-			ia2Sel.endObj,
-			ia2Sel.endOffset,
-			False
-		)
-		paccTextSelectionContainer.SetSelections(1, byref(r))
+		if not selInfo.isCollapsed:
+			selFields = selInfo.getTextWithFields()
+			ia2Sel = _Ia2Selection()
+
+			log.debug("checking fields...")
+			self._getStartSelection(ia2Sel, selFields)
+			self._getEndSelection(ia2Sel, selFields)
+
+			log.debug("setting selection...")
+			r = IA2TextSelection(
+				ia2Sel.startObj,
+				ia2Sel.startOffset,
+				ia2Sel.endObj,
+				ia2Sel.endOffset,
+				False
+			)
+			paccTextSelectionContainer.SetSelections(1, byref(r))
+		else:  # No selection
+			r = IA2TextSelection(None, 0, None, 0, False)
+			paccTextSelectionContainer.SetSelections(0, byref(r))
 
 	def clearAppSelection(self):
 		"""Clear the native selection in the application."""