You need a

NADAR

Relay Propagation Checker for bookmark Probably a local cache relay like nostr-relay-tray can help

GitHub

GitHub - CodyTseng/nostr-relay-tray: A nostr relay for desktop, available on macOS, Windows, and Linux.

A nostr relay for desktop, available on macOS, Windows, and Linux. - CodyTseng/nostr-relay-tray