Feditext beta users, today's TestFlight build 69 includes various fixes and workarounds for Firefish and Hajkey.
we will be working with server devs to get some of those fixed on the server side (for Hajkey's case, in Iceshrimp), so that future clients won't have to special-case anything.
known not to work in this release:
Hajkey's suggested accounts to follow: displays an error message
intermittent foreign key constraint error when browsing Firefish or Hajkey timelines: you don't need to report this one, we're already investigating