old.reddit is starting to come apart at the seams, tho. (maybe it's because r/subs don't keep the style sheets up to date or something? i dunno) in many cases you can't up or downvote, there's no search button, there's no sidebar with the flair and the rules/mods, etc.
I used "style sheet" in a generic sense, rather than to mean CSS (I remember Microsoft (Multitool) Word v1.0) and I was referring to the layout of a subreddit home page which I've never played with but I'm aware the moderators have some control over.
I know how to turn off Page Style in Firefox (manually for every page) which is CSS related, but otherwise have no idea what you are referring to