I modified Nos2x-fox's manifest.json to allow permissions for data access for just the following Nostr client for Firefox.

Created a signed .xpi file. Also, it's possible to install an unsigned xpi after you modify the extension from GitHub in Firefox > `about:config` > Set `xpinstall.signatures.required` to false. The only reason I've not done this is because I don't want some other unsigned xpi being installed maliciously if that is turned off.