we can deliver signature with the url, for example like this:
https://nostr.download/b59a2860fc3bc35f19e50a9841b0609e765e5c1b2b2298e2b2472df1c252b8e3#5b7eb7c870f44e90f5ce289caf5889fb1e9b30310faf84fedd82e6cd005f9bbfd3f15fe1a3b1e03466b28741a05eb96bb3946a411ef50fbc2a3c3e6683b1df3b