Fix crash from background access to style::icon-s.

Telegram/SourceFiles/ui/chat/chat_theme.cpp

@@ -444,7 +444,8 @@ void ChatTheme::setBubblesBackground(QImage image) {
 	_bubblesBackgroundPrepared = std::move(image);
 	if (_bubblesBackgroundPrepared.isNull()) {
 		_bubblesBackgroundPattern = nullptr;
-		_repaintBackgroundRequests.fire({});
+		// setBubblesBackground called only from background thread.
+		//_repaintBackgroundRequests.fire({});
 		return;
 	}
 	_bubblesBackground = CacheBackground({
@@ -459,7 +460,14 @@ void ChatTheme::setBubblesBackground(QImage image) {
 		_bubblesBackgroundPattern = PrepareBubblePattern(palette());
 	}
 	_bubblesBackgroundPattern->pixmap = _bubblesBackground.pixmap;
-	_repaintBackgroundRequests.fire({});
+	// setBubblesBackground called only from background thread.
+	//_repaintBackgroundRequests.fire({});
+}
+
+void ChatTheme::finishCreateOnMain() {
+	if (_bubblesBackgroundPattern) {
+		FinishBubblePatternOnMain(_bubblesBackgroundPattern.get());
+	}
 }
 
 ChatPaintContext ChatTheme::preparePaintContext(

Telegram/SourceFiles/ui/chat/chat_theme.h

@@ -163,6 +163,7 @@ public:
 	[[nodiscard]] const BubblePattern *bubblesBackgroundPattern() const {
 		return _bubblesBackgroundPattern.get();
 	}
+	void finishCreateOnMain(); // Called on_main after setBubblesBackground.
 
 	[[nodiscard]] ChatPaintContext preparePaintContext(
 		not_null<const ChatStyle*> st,

Telegram/SourceFiles/ui/chat/message_bubble.cpp

@@ -266,11 +266,6 @@ std::unique_ptr<BubblePattern> PrepareBubblePattern(
 	};
 	addShadow(result->corners[2]);
 	addShadow(result->corners[3]);
-	result->tailLeft = st::historyBubbleTailOutLeft.instance(Qt::white);
-	result->tailRight = st::historyBubbleTailOutRight.instance(Qt::white);
-	result->tailCache = QImage(
-		result->tailLeft.size(),
-		QImage::Format_ARGB32_Premultiplied);
 	result->cornerTopCache = QImage(
 		result->corners[0].size(),
 		QImage::Format_ARGB32_Premultiplied);
@@ -280,6 +275,14 @@ std::unique_ptr<BubblePattern> PrepareBubblePattern(
 	return result;
 }
 
+void FinishBubblePatternOnMain(not_null<BubblePattern*> pattern) {
+	pattern->tailLeft = st::historyBubbleTailOutLeft.instance(Qt::white);
+	pattern->tailRight = st::historyBubbleTailOutRight.instance(Qt::white);
+	pattern->tailCache = QImage(
+		pattern->tailLeft.size(),
+		QImage::Format_ARGB32_Premultiplied);
+}
+
 void PaintBubble(Painter &p, const SimpleBubble &args) {
 	if (!args.selected
 		&& args.outbg

Telegram/SourceFiles/ui/chat/message_bubble.h

@@ -33,6 +33,7 @@ struct BubblePattern {
 
 [[nodiscard]] std::unique_ptr<BubblePattern> PrepareBubblePattern(
 	not_null<const style::palette*> st);
+void FinishBubblePatternOnMain(not_null<BubblePattern*> pattern);
 
 struct SimpleBubble {
 	not_null<const ChatStyle*> st;

Telegram/SourceFiles/window/window_session_controller.cpp

@@ -1632,6 +1632,7 @@ void SessionController::cacheChatTheme(
 			this,
 			result = std::make_shared<Ui::ChatTheme>(std::move(descriptor))
 		]() mutable {
+			result->finishCreateOnMain();
 			cacheChatThemeDone(std::move(result));
 		});
 	});