Tester on Nostr: test nostr:note1x83frzdx34vemzwaustm4xxftt3g3xjef5yxuz7nzp9m2pnykmcs3gqkm7

quoting note1x83…qkm7

NUT-20 allows Cashu wallets to create "mint quotes" (intention to create new ecash) and lock that request to a user-defined public key. This allows third party services such as an LNURL server to create invoices for wallets that are offline without being able to rug the ecash created by paying that invoice.

https://github.com/cashubtc/nuts/blob/main/20.md