*The Gadget-Merge shouldn't allow merging items if one of the items has P31 = Q4167410 ("Wikimedia disambiguation page") and the other doesn't.
*The same goes for Special:MergeItems / the api function
| Item 1 | Item 2 | Expected result |
| Q4167410 | Q4167410 | merge |
| Q4167410 | not Q4167410 | don't merge |
| not Q4167410 | Q4167410 | don't merge |
| not Q4167410 | not Q4167410 | merge |
Project discussion: https://www.wikidata.org/w/index.php?title=Wikidata:Contact_the_development_team&oldid=361189082#Playing_around