If it helps, it really doesn’t care what certificate the page it signed with, whether that be localhost, Mozilla CA participants, or maybe even a future CA fork

If it helps, it really doesn’t care what certificate the page it signed with, whether that be localhost, Mozilla CA participants, or maybe even a future CA fork for Russia if that happens. Plaintext HTTP is just not advisable even on a private network when some inline network device like LAN turtle could be passively exfiltrating traffic.