If I have an app like Pidgin maximized and then close it, but it keeps running (like pidgin does, or thunderbird if you have a "close to tray" add-on), the top bar will stop responding to window actions like slide and double-click to restore window, middle-click to minimise, etc...
It also happens with Banshee, when you close it while it is playing (but only if it was maximized).
I think I've found the problem.
If I have an app like Pidgin maximized and then close it, but it keeps running (like pidgin does, or thunderbird if you have a "close to tray" add-on), the top bar will stop responding to window actions like slide and double-click to restore window, middle-click to minimise, etc...
It also happens with Banshee, when you close it while it is playing (but only if it was maximized).