Can't add component because class SphereCollider doesn't exist! (WebGL)

Questions & Answers
1

I was having an error with a WebGL build where the browser console was outputting the following error:

"Can't add component because class SphereCollider doesn't exist!"

I found this extremely confusing cause all I was trying to do was access the SphereCollider component on a freshly generated primitive. This issue was only occurring on the live WebGL, not in the editor.

Solution: It took me two days to discover that one or more files in my ftp upload was corrupted and my ftp software was not overwriting the previous files when uploading a build. The game would still run (mostly) but would have reality-bending nonsensical bugs like this one in the output.

P.S. I wrote this in order to answer my own question as documentation for the next person who suffers this issue.

2

Solution: Ftp software was not overwriting one or more of the previous files when uploading a WebGL build. Make double-sure the old files are getting overwritten.