Slight issue with {=$LastModifiedSummary}

Hello,

I have a slight issue with {=$LastModifiedSummary}, when used in pagelists.
I'm expecting the summary for the last edit only, when it exists ;
but in place of that, I am given a list of the summaries of recent
edits (but not all summaries from the beginning : only a few, and I
can not see what is the logical reason of the limited aggregation).
And, my Group.RecentChanges look all fine, showing the last summary, as normal.

I have an impacted test pagelist shown here :
https://www.languefrancaise.net/Test/LastModified
where pagelist is something like :

(:pagelist group=Bob,Tintin "Roland de L." fmt=#rdl1
order=-$LastModified count=30:)
[[#rdl1]]
*[[{=$FullName}|+]] | [[{=$FullName}?action=diff|diff]]
**{=$LastModifiedSummary}
[[#rdl1end]]

PmWiki website doesn't have this issue
(https://www.pmwiki.org/wiki/Test/LastModified)

It is quite a recent issue I guess but that's not something I would
have seen immediately as soon as it had appeared.

Might this come from recent $EnableMergeLastMinorEdit option (I don't use it) ?
LastModifiedSummary appears 2 times in my config for feed and for
notification and pmwiki version is 2.3.25.

Thank you,
Gilles.