Use showFullScreen() instead of using a flag

main.cpp

@@ -180,8 +180,7 @@ int main(int argc, char *argv[]) {
     worker.setMainWindow(&mw);
 
     mw.setWindowFlags(Qt::Window | Qt::FramelessWindowHint);
-    mw.setWindowState(Qt::WindowFullScreen);
+    mw.showFullScreen();
-    mw.show();
 
     return a.exec();
 }