Got very same issue after upgrading to Kubuntu 15.10 from 15.04. In my case it's nvidia.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1301125 Title: Lock screen after idle time freezes unity To manage notifications about this bug go to: https://bugs.launchpad.net/unity/+bug/1301125/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
