It's a draft: https://github.com/nostr-protocol/nips/pull/686. Looks like our NIP number got ganked.
nprofile1qqs99d9qw67th0wr5xh05de4s9k0wjvnkxudkgptq8yg83vtulad30gpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz9nhwden5te0v4jx2m3wdehhxarj9ekxzmny9uq3kamnwvaz7tmjv4kxz7fwdehhxarjwpkx2cnn9e3k7mf0j4msr2 (nprofile…msr2) it is a thing, I think 6+ clients support it already. We're just waiting for NIP 44 encryption to get finalized.