I also had problems in Edge (chromium). Works perfectly in Firefox.
It errors and refuses to continue at 'Press SPACE to start' or any of the 4 following 'Video playing event called's if there's no user input in a very short period prior to the call, even with the frame in focus. 'Press SPACE' shows at the same time as a video call, hence the lockup there.
Console error:
"Uncaught (in promise) NotAllowedError: play() can only be initiated by a user gesture. (anonymous) @runner.js:49"
You can get past it by clicking or pressing space constantly from end of loading til the game level appears, but I expect it'll happen again with any future video call.