Hi, thanks for researching so much so quickly. Yes, it's probably a browser issue, because I ran it on Edge and I am playing it now. Could have something to do with the adblock or the hardening... probably the latter (Although I haven't any trouble with other Unity WebGL uploads so far on the same browser and settings)
The game is so good. The art, the sound, the puzzles, the way you are teaching the player about the different mechanics... I sense the level designer has also binged all of Mark's videos on the topic. Extremely enjoyable.
It actually has a ton of polish already IMO. The art is super good, the sound is nice and engaging, and the gameplay is enrapturing. I think you should for sure work after the jam on this. Cheers!