Heyas,
First of all, sorry if that has been reported before, I searched my arse off but couldn't find any fitting thread.
It's happened to me twice today that upon trying to join a match, in the lobby I could neither choose my character nor leave the lobby again. Clicking the character selection button simply yielded no result (didn't behave like a button at all, no sound, no click animation, nothing), same goes for the "Yes" button in the "Are you sure" screen when trying to leave the lobby. Anything else worked flawlessly, just those buttons behaved erratically (and made me ask for a kick).
After trying to quit the game back to Windows directly after the second occurance of the issue (joined another game after the first and had a blast playing), I couldn't use that quit dialog either (again the "Yes" button) and had to kill the game via the task manager.
Any ideas?