Watching fullscreen embedded videos cancels TB games [CLIENT]

So I was watching the Zombie Slayer embedded YouTube video while waiting for people to ready up, and upon game starting I get a client error. Easily Reproducible.

1. Enter a TeamBuilder lobby and click ready, then go back to the main client menu
2. Start any embedded video in the client
3. Fullscreen that bitch
4. Watch in bewilderment as you return to the lobby upon gameload with a error titled "*game start error" with the description "*sorry, an error occured when attempting to start your game. Please try again later

Come on, man. I should be able to watch videos embedded and it not boot me out of a lobby. At least make the game load but stop the video or something.