Virtualmin always shows the IPv4 address twice in Server Configuration > DNS Options > Allowed sender IPv4 addresses and duplicates the ip4 mechanism in the DNS SPF record. I manually correct it for every virtual server.
This is a non-critical bug, if it is indeed that, and your spf records would work equally well had you not removed the redundant IP address.
Let’s try and calculate the benefit of your manually removing the redundant IP. When spf records are parsed, it would take someone else’s mail server a millionth of a second more to process the redundant IP in your spf record. Now if it takes you a couple of minutes to use Virtualmin to remove the redundant IP for every virtual server that you host, then that’s 120 seconds of your time: at a million parse operations per second, your two minutes effort will only benefit the internet in general when the number of parses to a spf record exceeds 120 million per virtual server that you host.
Oh, absolutely, one of the tiniest, cutest, most innocuous bugs I’ve ever seen. I just figured a bug is a bug and I might as well report it. It’s apparently been around for a while and it’s probably an easy fix.
Your impact analysis and housekeeping comment gave me a chuckle after a rotten day. Thanks for that.