The same for me, it froze, but also with a black screen, except one really shady object that looks a bit like a giant screw standing upside down, I can't even tell what it is. So I wasn't able to play it at all.
If you used GPUparticles, both their 2D and 3D variants, this might be the or at least one of the issues with lag / crashes on web. So you might better use CPUparticles. I made the experience in my previous jam game, which turned out to be the issue for my project.