I think it’s incredibly important that people know, with absolute certainty, whether or not the new Mozilla/Firefox privacy policy in any way applies to / covers such a service.

I’m not saying I know the answer- What I’m saying without a concrete, permanently applied answer it’s not even considerable.

You can’t know that with absolute certainty. Sorry, but if you’re using someone elses server for your communications and they’re not end to end encrypted, you should just assume that they can and do read your emails.