"native apps" here is for the Tor connection.

but extensions never can talk to any native app only the special installed and configured ones.

"the native application must grant permission for the extension by including the ID in the "allowed_extensions" field of the app manifest."

this is typically used password manages for example.

technical details: https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_messaging