Thanks for the help. That is a very different problem than I thought. It turns out the issue is because I forgot to skip the automatic sizing for the offline version in the browser build. The reason I wasn't aware of it before is because no one I knew had a screen with higher than 1920x1080 resolution, which is the condition to play in a bigger window. This should be fixed now.
I also added the drop through platforms ability. I think the only reason it wasn't there already is because when I coded the base gameplay I didn't know whether that would break any of my ideas for puzzles. I also added a second and a half on to the cave timer since I've heard from other people that it's too strict. However, I do want it to be challenging.
I can't really do the camera movement on switches, because the jank way I handled the image loading would result in massive pop-in. This was a consideration back when I made the game, which is why I made sure the sound would be directional.