I'm having trouble replicating this, even when I search for "Sandbox". It could be that it's an odd case and the results have changed since... Is it still happening?

Starting point:

Scroll down and back up:

Scroll down and back up again:

Scroll down and back up a third time:

(Note that the images shown in the gallery tool's search box are not necessarily CC-BY-SA, which is the Phabricator license. They should all be from Commons and available under a similarly free [or more free] license.)

Oy, it looks like the row-height calculation repeats itself unnecessarily on rows that are already built, and then "adjusts" the size unnecessarily - which makes the images bigger, and requires (ironically) more adjustment to fill in the row.

It might be that we call the rebuilding rows too much. I'll try to take a look, but if anyone wants to take this on, please do - I am a bit swamped with RCFilters at the moment.

@Mooeypoo No worries, I'll look into it - thanks for the pointers.

I have a sneaking suspicion that it has to do with this: https://gerrit.wikimedia.org/r/#/c/346645/

I think I removed a skip condition from line 363 that causes this. I'm not near a computer, but I'm hoping that helps. I think that condition should probably come back....

Yeah that's the culprit

Change 354129 had a related patch set uploaded (by Tchanders; owner: Tchanders):
[mediawiki/core@master] MediaSearchWidget: Only resize new results

https://gerrit.wikimedia.org/r/354129

Change 354129 merged by jenkins-bot:
[mediawiki/core@master] MediaSearchWidget: Only resize new results

https://gerrit.wikimedia.org/r/354129