Board Thread:Support Requests - Community Management/@comment-33279756-20171128120452/@comment-27345308-20171128160629

Actually, hiding page content yourself with a JavaScript script that's toggled by such a checkbox would be a customization policy violation, so that wouldn't work. "Content Warning" messages you get on some wikis are generated by a Wikia extension you can possibly request to enable through Special:Contact. Possibly.