Using QtWidgets on Android, QMenuBar does not paint correctly when using a mouse or stylus, rendering it effectively unusable.

When opening a menu and then moving the cursor over another menu, it will flicker open and then disappear. Sometimes it's still possible to select items from the invisible menu, leading to nested menus showing up in the void.

Staying on a single menu sort of works, but moving the cursor across the menu items causes strange effects with items being partially painted. This may be related to the same issue that QComboBox items have, see QTBUG-139194.

The issue makes Qt6 effectively unusable on Android for QtWidgets applications that want to use a real menu bar, leaving them stuck on Qt5.

I'll attach a video showing the issue on a Samsung S6 Lite running Android 13, but the issue seems to reproduce on any device.

The minimal application shown in the video is attached and also available here: https://github.com/askmeaboutlo0m/barebones-qt-app/