I think this could be related to the way that Unity intercepts and replaces Compiz minimize logic with its own.
Please try Gnome Classic and let us know if the problem persists there. If you don't yet have an option to log in to Gnome Classic at login then you need to install "gnome-session-fallback" first: sudo apt-get install gnome-session-fallback ** Changed in: compiz (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of compiz packagers, which is subscribed to compiz in Ubuntu. https://bugs.launchpad.net/bugs/1081889 Title: The minimize all windows shortcut doesn't work right To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1081889/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~compiz Post to : compiz@lists.launchpad.net Unsubscribe : https://launchpad.net/~compiz More help : https://help.launchpad.net/ListHelp