Comment 55 for bug 1316873

It looks like there may be more than one bug here. But let me narrow at least one of them down some. When it happens to me, my screen locker quits working. Both slock and xtrlock just blank the screen and exit. When run from a shell, I get an error message that they can't grab the cursor. Restarting the window manager clears up both problems, even if I don't end the session. Since that window manager is spectrum, the only part of the unity desktop that's running is lightdm.