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Persistently disable/re-enable custom subreddit styles via a userscript command
Adds a userscript menu command to persistently disable/restore a subreddit's custom CSS on old.reddit.com.
Note: this option is now built into Reddit if you're a) using old.reddit.com and b) logged in:
Unlike the built-in option, this userscript persistently toggles a subreddit's style on/off whether you're logged in or not.