[Client] Never loaded into champ select, game starts either way

Queue'd up for an ARAM game on EUW. After about 40 seconds a queue popped up. I accepted the queue, but I never got a response from the client (it got stuck at the ''Match accepted, waiting for other players'' screen (as shown in the screenshot). I thought the client would eventually throw me into champ select, but it never did. So after about 70 seconds the game screen suddenly popped up (in the background of the client, as seen in the screenshot) but I never actually made it to champ select.

I don't know how to reproduce the bug, but I suppose it has something to do with the new client since this has never happened to me before I switched over to this new client.

I'm not really going to complain about the ARAM loss, but I am pretty scared considering this may happen in Ranked aswell, which means you are forced to dodge the game considering you can't ban/pick/lock a champ.