Promoted queen disappearing in bullet games?

Is anyone aware of this bug:
In fast time control games, sometimes a promoted piece will disappear, forcing you to essentially play blindfold chess with that piece until the game ends. Just wanted to bring attention to this glitch. Thanks.

I played a rapid game and the Queens dissapeared just as you described. When I refreshed the page it said I left the game and the game was lost immediatly though the refreshing only took like 5 seconds.