Hi, I'm not sure what this means, but I had the same problem (pink shadows with an 8600M GT) and it was solved simply once I installed the package xserver-xgl (which wasn't installed).
sudo apt-get install xserver-xgl -- [nvidia 169.xx] gtk window decorator somtimes draws decoration ugly or not at all https://bugs.launchpad.net/bugs/186382 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
