I wrote this one to strip the custom css from any sub on (old) reddit. I use it on subs I find annoying, like mildlyinfuriating.
javascript:(function(){x=0;s=document.styleSheets;for(const y of s){if(y.title==="applied_subreddit_stylesheet"){if(y.disabled!=true){y.disabled=true;}else{y.disabled=false;}}x++;}})();