There is an experimental RFC currently being discussed: https://datatracker.ietf.org/doc/draft-ietf-httpbis-cache-di... The technique is derived from the H2O Casper work (and by the same author).

I have a Javascript service worker implementation here: https://www.npmjs.com/package/cache-digest-immutable

Note: This is still based on a Golomb-coded set (GCS). Current proposal under discussion is to use a Cuckoo filter. Takes slightly more bandwidth but allows removal when browser caches evict items.