WordPress 5.6 will ship with jQuery 3.5.1 and an updated version of jQuery Migrate, which will help you identify potential compatibility issues in your extensions. Developers should ensure extensions are compatible with jQuery 3 because the WordPress Core team is currently planning to phase out the use of jQuery Migrate in WordPress 5.7.
Earlier this year, the WordPress Core team shared the 3-phase plan they were implementing to upgrade WordPress Core’s bundled version of jQuery. That plan is currently in its second phase, which involves releasing WordPress 5.6 with jQuery 3.5.1 and jQuery UI 1.12.1. This release also upgrades WordPress Core to the latest version of the jQuery Migrate plugin, which gives specific advice about most of the major changes in jQuery 3 that may affect your code. You can also read additional details on deprecations and removals, and learn how to upgrade your code, by reading through the jQuery Core Upgrade Guide.
How can I test things?
There are instructions for debugging your code in a recent post from the WordPress Core team outlining phase 2 of the WordPress Core upgrade plan. In WordPress 5.6, you can load jQuery Migrate in debug mode by setting
How long do I have to make changes?
WordPress Core will be phasing out the jQuery Migrate plugin as early as WordPress 5.7 (pending additional testing), which is currently slated for release in March 2021. While there are still several months before that happens, we recommend starting your compatibility testing now in case it reveals unforeseen issues that need to be resolved in any of your dependencies.
You can follow along with the work we’re doing around jQuery 3 compatibility for WooCommerce in these related issues on GitHub. As we learn more, and as the final phase of WordPress Core’s jQuery 3 upgrade plan approaches, we’ll be sure to keep you updated here.
In the meantime, don’t hesitate to reach out to us in the comments section below or in the
#developers channel of our WooCommerce Community Slack.