I use Ubuntu 12.04 with gnome-shell and default Ambiance window theme. There is a display glitch on title bar of background windows. It can be seen on the screenshot below.
The bug also occurs with with Radiance window theme, and also when I use gnome-classic.
I must have messed with some configuration file on my home directory because this problem doesn't occur with another account (guest account in fact).
What can I do to simply get rid of this annoying display glitch ?
