Site warning: ERR_CERT_COMMON_NAME_INVALID or SSL_ERROR_BAD_CERT_DOMAIN

Symptoms

Opening a website over HTTPS, such as https://example.com, returns the following message:

• On Chrome-based browsers

  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

• On Firefox-based browsers

  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

The SSL/TLS certificate assigned by the domain has an incorrect name, or is the default one from the Plesk Panel.

Resolution

Re-issue the domain's certificate with the correct name, or issue a new one from scratch, following the instructions in this guide: How to install an SSL certificate for a domain in Plesk (Let's Encrypt / other certificate authorities)