In some cases, a message needs to be different for all languages wikis in a certain family. For instance, all Wikipedias might use 'article', while all Wiktionaries would use 'entry'.
If the order (highest precedence to lowest) was:
Local wiki
Family overrides
Code
that could solve this issue.
Version: wmf-deployment
Severity: enhancement
This should be relatively easy to implement with https://gerrit.wikimedia.org/r/#/c/98078/
Create a new i18n file in WikimediaMessages extension called i18n/wikipedia/en.json
Add a new variable to InitializeSettings, something like wmgUseWikipediaMessages. Set it true for Wikipedias. (Or make it generic like wmgSiteSpecificMessages.)
In CommonSettings, if that variable is set, add a hook similar to the one in the linked commit, but adapted for JSON and perhaps with additional performance tweaks if needed.
Thanks.
Done at https://git.wikimedia.org/blob/mediawiki%2Fextensions%2FGettingStarted.git/9be5988183fd7ef4a7e36423ef55876043510ccc/Hooks.php#L473 and https://git.wikimedia.org/blob/mediawiki%2Fextensions%2FGettingStarted.git/9be5988183fd7ef4a7e36423ef55876043510ccc/GettingStarted.php#L447 a while back.
Currently it only has custom behavior for Wikipedia, but it can be done for further families.
It's not a general solution, but I'm not planning on implementing a general one right now, so marking WORKSFORME. If you think there should be a general one, reopen.