–Qt: Fix a race condition in PainterGL that could lead to a crash

CHANGES

@@ -9,6 +9,7 @@ Bugfixes:
  - Qt: Use safer isLoaded check in GameController
  - GBA Memory: Fix DMAs from BIOS while not in BIOS
  - GBA: Fix idle skip state being retained between games
+ - Qt: Fix a race condition in PainterGL that could lead to a crash
 Misc:
  - Qt: Window size command line options are now supported
  - Qt: Increase usability of key mapper

src/platform/qt/DisplayGL.cpp

@@ -205,7 +205,7 @@ void PainterGL::start() {
 }
 
 void PainterGL::draw() {
-	if (m_queue.isEmpty()) {
+	if (m_queue.isEmpty() || !GBAThreadIsActive(m_context)) {
 		return;
 	}
 	if (GBASyncWaitFrameStart(&m_context->sync) || !m_queue.isEmpty()) {