You can’t block it for the search, but your instance Admins can. For example, sh.itjust.works defederated from hexbear.net, but I find many hexbear communities in Voyagers Explore page when sorting by top.
How to block dead Lemmy servers from search and interactions?
Submitted 3 weeks ago by Pro@reddthat.com to fediverse@lemmy.world
scrubbles@poptalk.scrubbles.tech 3 weeks ago
They’ll automatically defederate after a few days. As for search, it only searches your local instance and what is already there, so it’s just historical searches. It won’t be anything new.
nokturne213@sopuli.xyz 3 weeks ago
Really? I can still see posts from communities I am subscribed on long dead instances.
scrubbles@poptalk.scrubbles.tech 3 weeks ago
Defederate doesn’t mean it’ll delete the local history. Every post and comment is federated at time of creation to your instance, and will stay there as long as your instance keeps them. Defederate simply means it won’t receive future updates.