So I've seen this bug for quite a while now, but haven't seen anybody bring it up.
Basically, if you have your mouse hovering over a champion so that you see their splash art covering the enemy team, and their abilities covering the chat box, it won't go away if someone leaves the lobby before the game starts. What happens is you get kicked back to queue, the splash art remains on the right side of the window, and when you get back into lobby, the ability info is covering the chat.
Once you hover over another champ, to change the information displayed, and then remove the mouse, it goes away and you can utilize the chat again. But as everyone knows, that critical second or two prevents you from communicating with your team to inform them of what role you would like to play.
Now, any normal person, or just a decent human being, knows that the important thing is to work with your team to cover what you guys ned covered, and you don't always get the role you want. We've all dealt with greifers, however, and it makes the experience much less enjoyable.
Not a big deal, but I'm sure it's not intended.
1) Enter Champ select
2) Hover cursor over a champ to see detailed information
3) Someone on either team leaves while you have this information displayed
4) See splash art where it doesn't belong
5) Re-enter champ select after having been automatically put back into queue
6) You cannot see chat, nor enter text into chat, due to the ability information blocks covering the chat area
7) Replace your cursor over a champ, so that the information displayed is changed
8) Remove cursor from champion icon, and the information is removed
Next time this happens, I'll try to grab a screen shot.