Interesting. I'll see if I can reproduce and fix it. If you do play again, and encounter the problem. Try opening the chrome dev console (F12). If there's any red error messages in there it might pinpoint the problem. That's in case I can't make it black out for me.
Unfortunately, I couldn't reproduce this failure on my end. If it happens again, please open the dev console and see if there are any errors. Any little clue might help me pinpoint the issue. Whatever it is though appears to be very rare.
