Beehaw.org defederated themselves from Lemmy.world and sh.itjust.works. How does that impact their communities? Not much, as it turns out -- as long as you're not a user on those instances.
Community Search Tips
Where have Subreddits relocated? A directory of Subreddits' new homes
sub.rehab
Another Instance and Community Search tool: Lemmy Explorer at Lemmyverse.net
lemmyverse.net
Find communities using the feddit.de community browser
browse.feddit.de
Looking for a subreddit replacement? Try this unofficial subreddit migration list.
quippd.com
Someone built a Lemmy map!
lemmymap.feddit.de
Use the ALL listing at lemmy.ninja to find good communities
lemmy.ninja
Finding Lemmy Communities to Subscribe to: mining Lemmy.ml data