Menu items can be triggered with shortcut while modal dialog is open

There is a condition under which menu items will be shown disabled in the menu bar while a modal dialog is open, but the actions still trigger when using the shortcut:

1. The menu bar needs to be "shared" through all application windows (i.e. have no parent)
2. The action must have shortcutContext==Qt::ApplicationShortcut
3. The action must be added as a menu item into the shared menu bar

See the attached minimal example.
After removing any one of the conditions above, the behavior will be correct and the action cannot be triggered with the shortcut while a modal dialog is open.

Unfortunately that is the setup we have in Qt Creator (see linked bug).