I believe I might have nailed this down to either Conversation Essentials, Moderator Essentials, User Essentials or Bookmarks by
@Daniel Hood
Speculative but maybe true:
It seems XF out of the box shows 15 latest items in the "Postings" tab in member profiles.
I went thru a number of XenForo.com member profiles and all of them had 15 items in "Postings".
Now...
On my site, me and my other staff member had 6 items yesterday.
5 today.
It seems they are decreasing one by one, until "This member does not have any recent content" comes up.
The interesting bit...
On Daniel Hood's XenMods.com, many of the site's members have a varying number of posts within the "Postings" tab.
Daniel Hood has 6, Liam W has 1, Spinball has 5, etc...
Even though all of them have way more than 15 posts.
Maybe I'm wrong.
But, as far as I know,
@The Sandman uses a few addons by Daniel as well, and...
https://theadminzone.com/members/the-sandman.3/
Only one post in "Postings".
Even though he posted multiple times yesterday.
I don't know. Maybe I'm wrong.
But I checked other XF forums which do not appear to have add-ons by Daniel Hood, and they checked out fine (i.e. tha Postings tab had 15 recent posts).
@Mike @Brogan: if a member has, say, 100 posts (more than 15 anyways), is the 15 postings default on XenForo? Should it show 15 latest posts in the "Postings" tab on member profiles?
@Daniel Hood: I'd appreciate if you could check out if any of your add-ons potentially do something with the Postings tab (if those profiles on your site that have over 15 posts should show 15 posts in the Postings tab).