Example: http://commons.wikimedia.org/wiki/Special:Contributions/Casgliad has
"(Latest | Earliest) View (newer 50 | older 50) (20 | 50 | 100 | 250 | 500)"
but if you click on "never 50" you won't see more edits; you get "No changes were found matching these criteria."
This seems to happen on all WMF projects, e.g., it also happens on https://en.wikisource.org/wiki/Special:Contributions/Sharihareswara_%28WMF%29 , and on other MediaWiki instances as well. The reporter said:
<Trijnstel> it happens on every project (I noticed it on a private wiki)
However it is not happening on https://en.wikipedia.org/wiki/Special:Contributions/220.127.116.11 so maybe it's just for registered users and not IP addresses.
I've begun looking for changesets that touched relevant code in the past few weeks - https://gerrit.wikimedia.org/r/#/c/60571/ might be it.