When a shortcut is executed and QEvent::ShortcutOverride is processed to catch that event, the menu action is not triggered (normal, as expected), but the Mac menu title still "flashes" as if the menu action was executed. This is of course misleading for the user.
The attached example demonstrates the problem: Type 'A' in the edit control (trapped by QLineEdit, as any letter) and see the menu flashing each time.