I found this closed bug on Google while trying to troubleshoot the same issue. I can confirm that it happens randomly.
Switching to a virtual console and back with CTRL+ALT+F2 and CTRL+ALT+F7 causes metacity to resume normal behavior.
I found this closed bug on Google while trying to troubleshoot the same issue. I can confirm that it happens randomly.
Switching to a virtual console and back with CTRL+ALT+F2 and CTRL+ALT+F7 causes metacity to resume normal behavior.