Wondering about how webmentions would work on IPFS hosted sites? If there is no domain name to link the webmention to, then it simply won't work. An IPFS webmention would have to look at the content's CID hash instead to function. In theory this would actually be a much more precise way of identifying to what content a webmention belongs to; but in practice it would be hard as the CID change with every byte the content changes with. So a different approach would have to rely on the path set by the IPNS. The challenge there is that we can also use _dyndns txt entries. To be investigated.