I have no idea why though, but after a while playing, I can't chat anymore. I mean, the chat works and all and I see the messages, but when I write something and hit enter it won't show up.

Also the chat is quite laggy (in terms of typing something and having to wait until it appears). Same with my UI (though that's a known problem certain people have from what I can tell), which I'm just mentioning as it might be related, so maybe the new UI will fix the chat problem as well.