Hey all,
TL;DR: In MediaWiki 1.30, the jQuery library will be upgraded from 1.x to 3.x (with jQuery Migrate enabled by default). Read about this release and the API changes: https://blog.jquery.com/2016/06/09/jquery-3-0-final-released/ https://jquery.com/upgrade-guide/3.0/
== Upgrade guide ==
An overview of the important changes is available at: https://jquery.com/upgrade-guide/3.0/ This page also contains advice on how to migrate your code. In most cases it involves fairly simple changes, such as using a different method name, or adding quotes in selectors.
The vast majority of the added requirements and removed methods are restored through the jQuery Migrate plugin with a deprecation warning in the console. As such, it's unlikely your code will require any immediate changes.
If you do find a deprecation warning in the console, you can use the warning documentation to find out more: https://github.com/jquery/jquery-migrate/blob/ e967c3b98b/warnings.md
In MediaWiki 1.30, it will be easy to find uses of deprecated methods with the deprecation warnings. However, you don't need to wait for MediaWiki 1.30 to start migrating. The methods removed in jQuery 3 have been deprecated for a while already, and their replacements are already available in jQuery 1.x, today.
== Timeline ==
* April 2017: jQuery 3 lands in MediaWiki core master with jQuery Migrate plugin. * April to July 2017: Testing and fixing of issues detected during development. * July 2017: jQuery 3 enabled in Wikimedia's Beta Cluster. [1] * August 2017: jQuery 3 enabled on Wikimedia wikis in production.
jQuery 3 will also be released as part of MediaWiki 1.30.0 (expected in November 2017). [2]
As part of MediaWiki 1.30, inclusion of jQuery Migrate will made configurable so that sites that have already migrated may disable the plugin for better run-time performance.
Track progress at https://phabricator.wikimedia.org/T124742.
-- Krinkle
[1] https://www.mediawiki.org/wiki/Beta_Cluster [2] https://www.mediawiki.org/wiki/MediaWiki_1.30