For background see T284882#9251768
Problem:
We are using P218 (ISO 639-1 code) to determine the accepted spelling variant for a new Lexeme. We should switch that to P305(IETF language tag) to have larger coverage.
Additional info:
- Change needs to be made at https://gerrit.wikimedia.org/g/operations/mediawiki-config/+/4b29eca50dc9365f7e43a6ab8f782784ae1017c0/wmf-config/InitialiseSettings.php#9872
Acceptance criteria:
- Wikidata uses P305 instead of P218 to determine available language codes
How to test this:
- On Special:NewLexeme, selecting a language represented by an Item with a P305 statement but not a P218 statement automatically sets the language code instead of showing the spelling variant field, if the value is a code supported by MediaWiki