Comment 6 for bug 755403

I believe this in *no* duplicate of bug #745996. This other discusses "invisible" Unity stuff to which one can interact with the mouse. I've got no such thing. Nothing on screen I could interact with. If I click with any button in the screen areas where I assume a panel or Unity stuff to be, absolutely nothing happens (different from wht I get in the center of the screen, i.e. a contextual rigth-button menu that is the same).