I think I have this same bug. I originally suspected that it had something to do with chrome, since it always seemed to occur when I was browsing the net, but after reading your report, I now think the more likely candidate is eclipse, since I've always had eclipse open when the bug occurs. Perhaps the bug is caused by switching back and forth between workspaces using Ctrl-Alt-Left and Ctrl-Alt-Right (something I do often)? I suspect eclipse + switching workspaces may be occasionally breaking whatever handles window focus.
I have reproduced this bug on two machines, both of which were using eclipse at the time. I can usually fix the problem by closing chrome (and any other programs, except for eclipse) using Alt-F4, but I'm not sure if that always works. Here's some basic information on one of the machines, a Lenovo T500 Thinkpad: $ lsb_release -rd Description: Ubuntu 10.10 Release: 10.10 $ apt-cache policy xorg xorg: Installed: 1:7.5+6ubuntu3 Candidate: 1:7.5+6ubuntu3 Version table: *** 1:7.5+6ubuntu3 0 500 http://us.archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages 100 /var/lib/dpkg/status $ apt-cache policy compiz-gnome compiz-gnome: Installed: 1:0.8.6-0ubuntu9.1 Candidate: 1:0.8.6-0ubuntu9.1 Version table: *** 1:0.8.6-0ubuntu9.1 0 500 http://us.archive.ubuntu.com/ubuntu/ maverick-updates/main amd64 Packages 100 /var/lib/dpkg/status 1:0.8.6-0ubuntu9 0 500 http://us.archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages $ apt-cache policy compiz compiz: Installed: 1:0.8.6-0ubuntu9.1 Candidate: 1:0.8.6-0ubuntu9.1 Version table: *** 1:0.8.6-0ubuntu9.1 0 500 http://us.archive.ubuntu.com/ubuntu/ maverick-updates/main amd64 Packages 100 /var/lib/dpkg/status 1:0.8.6-0ubuntu9 0 500 http://us.archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages $ uname -a Linux clark-laptop 2.6.35-24-generic #42-Ubuntu SMP Thu Dec 2 02:41:37 UTC 2010 x86_64 GNU/Linux I've had this bug crop up while running both the integrated (Intel) and discrete (ATI Mobility Radeon HD 3650) graphics cards on my laptop, well as when using my desktop's Nvidia card, so I don't think it's related to any graphics driver. I also don't think it's related to compiz, since I've been able to reproduce this bug using metacity. Let me know if I need to post any more information! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/684503 Title: GUI becomes partially unresponsive -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs