Board Thread:Support Requests - Designing Your Wiki/@comment-45308935-20200724094450/@comment-9605025-20200724222230

My guess would be a general favicon design site. The instructions assume the user is the owner of the site and has access to source HTML. This is not the case for Fandom wikis since Fandom, not the wiki's founder, is the owner of the site. Users must upload the favicon via ThemeDesigner, as TableWiz and Fandyllic mentioned.