Help for some reason when I try to run my game in webgl, it keeps giving me this error.I don't know what to do.

Are you using unofficial unity packages?

I don't think a web build is essential, but just preferred for time and space reasons.

No im pretty certain im not using unofficial unity packages.I just really want to submit it as webgl, but if I cant by soon, then I will just upload it as the normal downloadable version.