QWidgetAction stays visible after trigger()

Question

I have a a QWidgetAction which holds a QWidget composed of a QLineEdit and a QPushButton. Once the user press the button the QWidgetAction call the trigger slot.

Now I have a QMenu which I activate with exec. The problem is that even though trigger is called (I've connected it to a print function as well to check) the menu won't close.

Regular QActions works well.

Any idea why?

P.S. Googling this issue I came across people with the same problem, but no solutions.