Bug 376180

The new global application menu does not allow easy switching of (sub)menus.

Expected behavior:
When I open a menu (e.g. File), the user should be able to switch to the next one (e.g. Edit) simply by moving the mouse.

Current behavior:
The first menu must be closed explicitly by clicking somewhere else before the user can switch to another menu.

Motivation:
It happens very often that I don't quite remember which application menu a certain action was in, that the application is new to me and I want to explore the menu or that I accidentally opened the wrong one.
The easiest way to quickly browse through different (traditional) menus is to simply move the mouse to the next menu.
With the new global application menu, this isn't possible which makes the global menu extremely tedious to use.