I've gotten this as well - it appears to be an empty context menu that somehow doesn't get destroyed.
To see what I mean, uncheck 'enable wireless' in the right-click menu of nm-applet, then left click the nm-applet. You'll see a tiny square appear - it's the empty network list context menu. Sometimes it stays, sometimes it vanishes when losing focus. It only seems to stay on the screen indefinitely when the network list gets refreshed while you have it open. Someone's forgetting to destroy a context menu before creating a new one! -- nm-applet leaves 5x5 pixel grey artifact on the screen near the panel https://launchpad.net/bugs/48711 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
