There are several related changes to snak hashes which should be announced:
- API output will include hashes in all snaks, due to Ia143563ed1. This is a significant change, which was announced on 2017-09-11.
- The goal of this is to include snak hashes in the HTML. That’s not a stable interface, but we might as well announce it along with the above change, since it will probably be deployed together.
- Special:EntityData will remain unchanged for now (thanks to I95cd7d1f9c), but we would like it to include hashes in all snaks as well. That would be a significant change.
- The dumps will also remain unchanged for now, but unless we go for two kinds of dumps (T174029), we probably want to remove snak hashes from them. That would be a breaking change.
(Note: I don’t expect anyone to rely on these hashes currently, so they’re significant and breaking changes in theory, but I don’t expect any breakage.)
We need to figure out when to make/deploy these changes and when to announce them.