@Gigi I have more Castr PRs for your consideration:
I think the NIP-53 works now too:

GitHub
Default to defaultRelays if none are found in the identifier by ericpp · Pull Request #18 · dergigi/castr.me
GitHub
Improve speed of npub page through batch loads by ericpp · Pull Request #19 · dergigi/castr.me
GitHub
feat: add nip-53 live streams/recordings by ericpp · Pull Request #9 · dergigi/castr.me
Vibe coded support for NIP-53 Live Activities (e.g. zap.stream, tunestr.io) in keeping with the vibe of the repo