This happens for me as well.Im using proprietary nvidia driver and 64 bit ocelot.
Steps to reproduce: 1.Open any application 2.Maximize it 3.Minimize it 4.Artifacts are visible in the top left corner screencap attached. Am fully updated as of now.I havent tested this with the open source nouveau driver though ** Attachment added: "screenshot" https://bugs.launchpad.net/ubuntu/+source/unity/+bug/847523/+attachment/2390302/+files/Screenshot%20at%202011-09-12%2015%3A33%3A53.png -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/847523 Title: artefacts left on screen after minimising window To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity/+bug/847523/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs