@Pawlicker@EricZhang456@atlas_core Signed fetches are a prerequisite for whitelist federation in Mastodon, and since with whitelist federation it'll drop internal fetch actors from non-whitelisted instances, nothing would federate outside of it. Considering their posts got fetched even on fucking poast, I doubt they have any blocks or whitelists in place, maybe only the "limited" option that hides all posts unless you're logged in and subscribed to set user. Might be a fluke due to traffic spike.