When I have watched a video online (usualy with YouTube video's), be it with Firefox or Chrome and press the button to exit full-screen mode, my laptop screen turns grey and there seems to be nothing I can do about it but enter TTY2 with ctrlaltf2, login and type sudo restart lightdm
and log back in, resulting in loss of work.
I own an ASUS N76VM laptop and it's running Ubuntu 12.04.
Offcourse I don't want this to happen and I'd rather make it so that it doesn't happen; instead of a sollution for after it has happend, but any sollution rather then restarting LightDM
would make me happy.