if hoverring on a submenu in QMenu, we will get Leave events

In a QMenu there are submenus and actions. If hovering on a submenu item, the submenu will be shown, and we will get leave events from almost all widgets, and not any new enter event. What expected is, as long as the mouse is inside the menu, no leave events should be raised.

Small example code is attached. The dock widget contains a menu. The central widget of the main window shows all Enter and Leave events of the qApp.

How to repeat:

1. move mouse into the dock widget on the left, we see Enter events in the plain text widget
2. hover mouse on submenu item 'menu2', the submenu will be drawn, and we will see the  QEvent::Leave events in the plain text widget. (Remark: no need to hover on 'action2')