User blog comment:MisterWoodhouse/Social Activity, the 2010 Editor, and Unpausing Migrations/@comment-34918040-20201013134801/@comment-34918040-20201013220833

I just got an honest answer to my ticket. It is because Fandom added a custom extension that overrides basic wikitext functionality. Untested, as it seems. How naive can one be? That's totally unacceptable.