Symptoms
Unable to open a site over HTTPS, i.e. https://example.com shows:
In Chrome browser:
Your connection is not private
Attackers might be trying to steal your information from example.com (for example, passwords, messages, or credit cards). Learn more
NET::ERR_CERT_COMMON_NAME_INVALID
This server could not prove that it is example.com; its security certificate is from domain.tld. This may be caused by a misconfiguration or an attacker intercepting your connection.
Proceed to example.com (unsafe)
NET::ERR_CERT_AUTHORITY_INVALID
In Firefox browser:
Your connection is not secure
The owner of example.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
example.com uses an invalid security certificate. The certificate is only valid for domain.tld
Error code: SSL_ERROR_BAD_CERT_DOMAIN
Error code: MOZILLA_PKIX_ERROR_SELF_SIGNED_CERT
Cause
An incorrect name in the SSL certificate on the domain or the default Plesk certificate is used.
Resolution
Renew the certificate for the domain with the correct name or issue a new one from scratch:
How to install an SSL certificate for a domain in Plesk (Let's Encrypt / other certificate authorities)