Just use only VPN to access your services behind the reverse proxy, if you want prevent unauthorised connections.
CA certificates are not here to prevent someone accessing a site, they are here, so that you can be sure, that the server you are talking to is really the one belonging to the domain you entered and to establish a tunnel in order to send the API calls (html, css, javascript etc.) and answers encrypted.
atzanteol@sh.itjust.works 3 months ago
No worse than protecting your ssh key. Just keep it somewhere safe.