"A password is required to enter this room" messages.
Today, having played multiple game modes, in the post game lobby after every game I have two messages that cover up the "Advanced Details" button and part of my champion icon. These messages say "A password is required to enter this room." There are two of them that say the same thing stacked on top of each other. When I click the "x" to get rid of them, they immediately pop back up. Sometimes when trying to "x" them the client freezes. One time there was even a bug splat.