I've noticed some games (such as https://krajzeg.itch.io/dank-tomb... and my current game I'm working on) perform very poorly in Firefox on Mac - low and uneven frame rates. The same games run fine on Firefox/Linux and Chrome or Safari on Mac.

Is this a known issue for Pico8, or is there anyway I can troubleshoot this?

In the browser's dev console it starts with >codo_init, platform: Emscripten

So perhaps it's an Emscripten issue and I'll have a look over there.

Thanks!