Unity users: Any good experience using URP and WebGL? Everything I do lags!

I'm trying to make a 3D game using Unity's Universal Render Pipeline, and I'm targeting WebGL because it's super convenient for game jammers to play and rate. Every build I make seems to get only like 15 FPS, and that's literally with like a character on a flat plane with one light, no post-processing, and that's it. Any tips for better performance on WebGL?