It’s a pretty blunt instrument and using it risks bringing in a lot of weird stuff you didn’t expect so there is a keyword filter to screen out some of the more jarring communities. The keywords are: ‘shit’, ‘piss’, ‘fuck’, ‘cunt’, ‘cocksucker’, ‘motherfucker’, ‘tits’, ‘greentext’, ‘4chan’, ‘fauxbait’. Any community with those words in it cannot be accidentally added while pulling in dozens or hundreds of others. View source code.

You can still manually add any community, including ones with those words in them (like “shitposts@piefed.world” or “4chan@sh.itjust.works”. Do this by going to the main Communities page and clicking on ‘Add remote community’.

While no communities I'd be interested in are affected by the filtered word list, requiring instance owners to know about and manually import each community affected by it still amounts to a built-in, non-optional block on most impacted communities (given that most communities realistically won't be manually imported); ideally the word list should be configurable as the other settings are.

Hope to see more entries in the series to come