When I modify a site link, another unrelated site link that I didn't touch also gets removed.
Steps to reproduce:
- make an item with en label "Map"
- add some site links: enwiki => Map, jawiki => 地図, arwiki => خريطة (seems I have reloaded the page here, perhaps after step #2)
- add another site link: dewiki => Karte (Kartografie)
- change enwiki site link: Map => Maple syrup
all is good at this point, but then:
- change enwiki site link back: Maple syrup => Map and along with updating the enwiki sitelink, the dewiki one gets removed in the same diff. I did not touch that one.
It shows as deleted in wb_items_per_site in my repo and in the diff being reported in the change propagation stuff. The site link is there in the DB during step 3 and 4, and enwiki, jawiki and arwiki site links are still there after step 5.
If I reload the page after step #3, the site link does not get removed in step #5.
If I add more than one site link (e.g. dewiki and eswiki) between step #2 and #4, then both of them get removed in step #5.