How to allow HTTPS and configure SSL certificate on domain in Plesk which has Hosting Type set as Forwarding?

Question

How to allow HTTPS and configure an SSL certificate on a domain in Plesk which has Hosting Type set as Forwarding in Domains > example.com > Hosting Settings?

Answer

Warning: Currently, it's possible to secure a forwarding domain only when Nginx is installed and enabled on the server. 

To secure a domain with Forwarding hosting type with an SSL certificate perform the following:

1. Connect to the server via SSH/RDP.

2. Check if the Common Challenge directory is enabled on the server.
   If the output of the command is as below:

   # plesk ext sslit --common-challenge-dir -info
   - Available: true
   - Enabled: false

   Execute the next command to enable Common Challenge directory:

   # plesk ext sslit --common-challenge-dir -enable

3. Log into Plesk.

4. Go to Domains > example.com > SSL/TLS Certificates where example.com is a domain with hosting type Forwarding and install a Let's Encrypt or the certificate from 3rd party certificate authorities.