[Client] Can't select anything after updating today (12/14)

https://i.gyazo.com/4d931650bff65ede56eee8191a6660df.jpg

Updated to v7.24-65251154.6525000 today.

I got a bunch of messages upon login that: several friends received their gifts (Baron BE icon), I received a gift (Baron BE icon), First Win of the Day is available, and a Key Fragment for Keeping it Sportsmanlike. So I closed them all, and now I can't click on anything. I suspect that strange box in the top left has something to do with it.

Closed the window, client asked me if I was sure and I was able to click Yes. Reopened and logged in and now everything's working again.