Same error except this time, it's complaining about gzip instead of br. Chances are I don't have something on my system that other people that can play this have. I appreciate the attempt to fix it though.
Site caching is a browser feature. Found a link to describe, how to do it, and only for a specific site.
And a little note from myself, I did notice that "jump" sound is played whenever button pressed, but if I spam it mid-jump, trying to get over croud in spa, it might be a little annoying. So a simple condition check "play sound if character grounded" would be great (or "play sound if char vertical speed is zero,", pick whatever suits you)