Er, is Mastodon actually using only IPv4 in the background? Trying to spin up an instance that had v4 firewalled out and couldn't follow from that instance, nor could I search that instance from another (to a host I know has working v6). Unfirewalled v4 and it all worked.
@noodles I was surprised to see in my profile that mastodon.social is ipv4-only
@noodles Did your server name resolve to the v4 as well as the v6 address while it was firewalled? If so, it might just be a question of priority.