Skipping domain validation

Can someone help me? I have a few questions.
I’m using this guide https://github.com/nextcloud/all-in-one/blob/main/reverse-proxy.md

  1. If I use --env SKIP_DOMAIN_VALIDATION=true, then should I add a self-signed certificate somewhere? Because over https I get the SSL_ERROR_RX_RECORD_TOO_LONG error, and over http I try to log in with my username and password from AIO interface :8080, but nothing happens.
  2. Is there a config somewhere that references an ssl certificate?
  3. In a scenario without --env SKIP_DOMAIN_VALIDATION=true, where is the Let’s Encrypt certificate stored? GitHub - nextcloud/all-in-one: Nextcloud AIO stands for Nextcloud All-in-One and provides easy deployment and maintenance with most features included in this one Nextcloud instance.
  4. I mean, what should I do if I already have a certificate for my domain?

Hi, I guess you are looking for this?