I think this is the only specific commit mentioned in my mastodon thread (https://mastodon.social/deck/@emaste/111229158907039679) that is still not in the release notes.
Graham mentioned that we should have a gpart bootcode caution, https://mastodon.bsd.cafe/@grahamperrin/111239333951787203 and also had other notes in https://mastodon.bsd.cafe/@grahamperrin/111265695742760546 that I haven't yet looked at.
I am also looking at highlights of changes that were already in 13.1 or 13.2 and will discuss those in a separate review.