Documentation has been updated and need translations: https://www.mediawiki.org/w/index.php?title=Special:Translate&group=page-Help%3ANotifications%2FCross-wiki&language=&action=page&filter= 

During the beta phase, the cross-wiki notifications feature was enabled by over 18,000 accounts across more than 360 wikis. We receive great feedback from a lot of very happy users. After that 3-months long beta period during which we made adjustments, that feature will be released by default on May 12 at 23:00 UTC.

Users who don't want to receive cross-wiki notifications can turn them off at individual wikis. More information is available on the documentation. The talk page is still open for any questions or feedback.

Do not hesitate to spread that information on your wiki! :)

Thanks,

Benoît
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