i entered a channel and was immediately kick/banned by a bot. i could not leave the room as CZ reported "#room: you're not in that channel". this is true, but CZ would not allow me to close the room window. and i had no way to re-enter the room to try leaving myself which would close the window automatically.
You can use View->Close to close it. *** This bug has been marked as a duplicate of 161597 ***