A QWidget inside a QMenu using QWidgetAction does not always receive enterEvent and leaveEvent.

What I did :

I implemented a custom widget to add inside a QMenu using QWidgetAction.

I wanted this widget to have a darker background on mouse hover.

I implemented enterEvent and leaveEvent to achieve this.

What I expected to happen :

When my mouse leaves a widget and enters another one, I expect the widget my mouse leaves to receive a leaveEvent and the widget it enters a enterEvent.

What happened instead :

This works most of the time, but for some reason sometimes an item does not receive an enterEvent or a leaveEvent, resulting in :

• an item that is not hovered anymore still having a darker background
• an item that is hovered not having a darker background

Additional informations :

It's not related to my custom widget implementation. This bug is reproductible with any widget. Replacing my widget by a QPushButton will result in the button sometimes not receiving mouse leave events and staying hovered.