↳ In-reply-to » @zvava @lyse I also think a location based reference might be better.

Here is just a small list of things™ that I’m aware will break, some quite badly, others in minor ways:

1. Link rot & migrations: domain changes, path reshuffles, CDN/mirror use, or moving from txt → jsonfeed will orphan replies unless every reader implements perfect 301/410 history, which they won’t.
   
2. Duplication & forks: mirrors/relays produce multiple valid locations for the same post; readers see several “parents” and split the thread.
   
3. Verification & spam-resistance: content addressing lets you dedupe and verify you’re pointing at exactly the post you meant (hash matches bytes). Location anchors can be replayed or spoofed more easily unless you add signing and canonicalization.
   
4. Offline/cached reading: without the original URL being reachable, readers can’t resolve anchors; with hashes they can match against local caches/archives.
   
5. Ecosystem churn: all existing clients, archives, and tools that assume content-derived IDs need migrations, mapping layers, and fallback logic. Expect long-lived threads to fracture across implementations.