The plugin register. Used on 8 million+ sites
Classic Editor
No known security flaws are listed for Classic Editor at the moment. New ones are found every week, which is what the morning watch is for.
Is your site on a safe version?
Be told the day a new one is found.
Mendbird checks your site every morning against the lists of known flaws, and emails you in plain English the day one hits something you run. Free for 14 days, then £9 a month.