nixpkgs/pkgs/applications/misc/keepassxc/firefox-native-messaging-host.json

{
    "name": "org.keepassxc.keepassxc_browser",
    "description": "KeePassXC integration with native messaging support",
    "path": "@out@/bin/keepassxc-proxy",
    "type": "stdio",
    "allowed_extensions": [
        "keepassxc-browser@keepassxc.org"
    ]
}