This was fixed (or it looks like it is) by setting compiz configuration to default and using the predefined configurations in ubuntu. Maybe going from 0.7.8 to 0.7.9 made some plugin doing that mess. I'm still not sure about which plugin was the cause of the problem, I'll investigate further.
** Changed in: compiz (Ubuntu) Status: New => Fix Released -- compiz freezes X when some applications are used https://bugs.launchpad.net/bugs/332549 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs