Creating new item from link using
https://www.wikidata.org/wiki/User:Yair_rand/WikidataInfo.js gadget
causes incorrect labels when I use this gadget on other wiki than with my language

When I create link from cs, language is set to cs (my home wiki).
But when I create from en or e.g. jv, language is set to cs too
https://www.wikidata.org/w/index.php?title=Q28111817&oldid=423746073

probably related T108907