Alt+Tab on screen display not disappearing

[Ryan Lerch]

Just wondering if anyone else has experienced in F18 (GNOME3.6) a weird 
bug where the alt+tab switcher does not disappear?

When it happens, i can press press alt+tab again and other switcher is 
displayed under (z-index wise) the one already on the screen. If i keep 
pressing alt+tab, these layer up also.

The annoying part is that when you go to restart the shell, (with 
alt+f2), that overlay does not get keyboard focus, so you can't restart 
it from there. The only way to restart the shell is to switch to another 
tty, and kill the gnome-shell process with kill -9

anyone else experiencing this issue?

cheers,
ryanlerch