Allow Null MX records
A Null MX record is a way for a domain to state that it doesn't accept any emails.
If a domain has no MX records, the A or AAAA record is used as a fallback instead.
Currently, cPanel does not accept a Null MX record.
To allow for Null MX records, the DNS administrator has to create an MX record with priority 0 and a dot (".") as the target.
As a cPanel user who does not need to accept email, it would be great if cPanel supported Null MX records. There's no reason that the server should spend time and resources trying to deliver emails for a domain that doesn't want to accept emails.