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@cleo @ada @puniko @tost there have been multiple issues complaining about how fedi does both link previews and also Deletes. sometimes to servers that arent even fedi anymore. the "health check" is a good idea to mark certain domains undeliverable bc i think either masto or oma sill keep trying basically forever. i ran a nextcloud social briefly and it still gets requests. i forget which magic HTTP response code will get mastodon to stop, and idk what others do