Does it happen with right-click too or just left-click? Does it happen with any other programs?
Do the old menus that are shown actually "work" -- that is, can you click items on them? Or are they just graphics artifacts left on screen?
I don't click any mouse button. I press the hotkey for the menu, move the mouse and press the hotkey again, move the mouse again and so on.
This bug occurs in Notepad++, Notepad, WordPad, Word, Firefox,... seems to occur in every program.
The old menus are not clickable, but strangely they react to the hotkey for showing/hiding the menu.