https://www.wikidata.org/wiki/User:Alicia_Fagerving_(WMSE)/sandbox.js

The API returns an edit-conflict error when saving some statements. In particular, this seems to occur when the API returns more than one statement of a particular type, in which case only one of them is saved.

For example https://booktool.toolforge.org/api/11655186 returns two wikidata-item statements (author and illustrator) and two string statements (isbn 13 and libris uri), but only one from each pair gets saved.