As near as I can tell you recently switched to VanillaForums . It appears that many of the features are not enabled https://docs.vanillaforums.com/help/addons/advanced-editor/
I find myself spending way to much time trying to figure out how to post a comment.
[[Forum - Guide]] seems like the right place to put this information.
I have updated that page with the items I would like to know how to do.