What were you trying to do that didn't work?

A customer reported some discrepancies when configuring a property multiple times: sometimes only the first property value is considered, sometimg it's the last property value.
From my latest testing (see the comment), MaxStartups, PerSourceMaxStartups, PerSourceNetBlockSize and IPQoS are affected.

Upstream is behaving correctly.

What is the impact of this issue to you?

Potential compliance issues

Please provide the package NVR for which the bug is seen:

openssh-server-8.7p1-46.el9
openssh-server-9.9p1-12.el10_1

How reproducible is this bug?

Always

Steps to reproduce

1. Create 2 snippets for MaxStartups

   # echo "MaxStartups 11:11:11" > /etc/ssh/sshd_config.d/11.conf
   # echo "MaxStartups 12:12:12" > /etc/ssh/sshd_config.d/12.conf
   

2. Check what is used by sshd

Expected results

# /usr/sbin/sshd -T -f /etc/ssh/sshd_config | grep -iw "maxstartups"
maxstartups 12:12:12

Actual results

# /usr/sbin/sshd -T -f /etc/ssh/sshd_config | grep -iw "maxstartups"
maxstartups 11:11:11