Comment 1 for bug 1917677

It is highly unlikely that the configuration file on one distro is replaced with one that was shipped on a different one. It may be a bit more likely that a config file is overwritten by a variant from a previous release, but I think this is still unlikely and I believe trimming the md5sum list is not a general practice for UCF managed configuration files.

As an example openssh-server ships the historical list, too:
$ cat /usr/share/openssh/sshd_config.md5sum
# Historical md5sums of the default /etc/ssh/sshd_config up to and including
# 1:7.3p1-5.
0d06fc337cee10609d4833dc88df740f
10dc68360f6658910a98a051273de22c
11f9e107b4d13bbcabe7f8e8da734371
16c827adcff44efaca05ec5eea6383d7
2eeff28468576c3f2e538314e177687b
386c8b9079625b78f6d624ae506958ae
38fc7b31b3e3078848f0eec457d3e050
395c5e13801f9b4f17c2cb54aa634fbd
...