Yesterday, we released a platform-wide upgrade to WordPress 5.5. Since then, we’ve noticed that some customers experiencing incompatibility issues with custom JavaScript code. This post is to help those customers understand the upgrade and how to resolve issues that may have come up.
If you are seeing new issues such as broken widgets or buttons in your editor, unresponsive buttons like “Publish,” broken page functionality that relies on JavaScript, or new errors in your browser console, these issues may be related to the platform upgrade.
The quick fix
We recommend installing and activating the jQuery Migrate Helper plugin to see if that resolves the issue first. This immediate fix has helped most customers facing issues after the WordPress 5.5 upgrade.
Why are these issues happening?
jQuery is a popular JavaScript library in use on many websites, and included in part of WordPress core.
The WordPress Core team is in the process of upgrading the version of jQuery (1.12) that is bundled with WordPress to the latest release (3.x). Upgrading jQuery brings many security and performance-related improvements. However, it can also introduce breaking changes for customers using older versions. To allow for a safe and smooth transition, the Core team has planned to manage the upgrade over several core releases.
The removal of jQuery migrate 1.x in the WordPress 5.5 release is the first step in this process. Customers that have custom code or plugins that rely on jQuery features that were removed or deprecated prior to jQuery v1 may run into issues like JavaScript errors.
The current schedule for updating the versions of jQuery in WordPress core is laid out in this WordPress Core development note. Following the recommendations of the jQuery team, this update will happen in the following stages:
- Remove jQuery Migrate 1.x. This was released on August 11th, 2020 with WordPress 5.5.
- Update to the latest version of jQuery and add the latest jQuery Migrate.
- This is tentatively planned for WordPress 5.6, depending on test results. (December 2020)
- Updating to the latest jQuery UI, version 1.12.1, is also planned for 5.6. (December 2020)
- Remove jQuery Migrate. This is tentatively planned for WordPress 5.7 or later, depending on testing. (Spring 2021)
How do I fix this problem?
For an immediate fix: we encourage you to install the jQuery Migrate Helper plugin. This is a short-term fix intended to give your team time to resolve compatibility issues.
For a longer-term fix: we suggest removing this plugin on your development environments, and resolving JavaScript errors there. Once you have your fixes, you can push them to your production environment and deactivate the helper plugin.
To test these changes, there is a plugin that can simulate the changes to different versions of jQuery bundled in code. We encourage you to test the updates well in advance of the pending changes coming in WordPress 5.6, currently scheduled for the end of the year.
How can I prevent compatibility issues from happening in the future?
As part of our managed WordPress service, we are committed to testing and deploying the latest version of WordPress on schedule to keep your site stable, performant, and secure.
Our automated testing catches some issues, however many of the issues with jQuery upgrades happen at the customized application layer. For instance, if you are using plugins that have JavaScript-based customization of your wp-admin screens, you might see breakdown in custom functionality.
For this reason, we encourage everyone to:
- Subscribe to email updates from this Lobby, which includes calls for testing for WordPress upgrades.
- Upgrade your non-production environments to test WordPress release candidates on your environments; you can open a support ticket to request an upgrade.
We will continue to improve our communications to better prepare you for Core releases. If you have suggestions about how you’d like us to contact you, please let us know.
Please don’t hesitate to reach out to the VIP team and open a support ticket, if you need further assistance.
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