Event handler bug

[Fifi]

I found a bug, probably in the event handler. When you join a server, join the game, click [Connect dummy], press [Spectate] and wait with releasing the mouse button until [Spectate] changes its label to "Join game" (it's delayed a bit, because a dummy doesn't join a server instantly after clicking [Connect dummy]) - the game stops reacting to the mouse buttons, presumably because one can't stop pressing a button which isn't on screen anymore.