Updating Outdated Jquery Versions In Premium WordPress Themes
Premium WordPress themes often bundle customized versions of jQuery for additional functionality and browser compatibility. However, failure to update these bundled jQuery versions can lead to problems.
Why Update jQuery
There are a few key reasons it is important to stay updated on the jQuery versions used in your WordPress theme:
Security Vulnerabilities in Outdated Versions
Like all software, vulnerabilities in jQuery are discovered and patched over time. Using an outdated jQuery version exposes your site to more potential attack vectors. Exploits targeting older jQuery vulnerabilities can compromise your site.
Missing Features and Fixes in Newer jQuery Versions
The jQuery project is actively developed and newer versions add useful features, performance enhancements, bug fixes, and browser compatibility updates. By updating jQuery, premium themes can benefit from 3+ years of improvements.
Incompatibilities With Modern Plugins and Themes
Many modern WordPress plugins and themes assume sites are running current jQuery versions. Running outdated jQuery can cause conflicts resulting in JavaScript errors, breakages, or limited functionality.
Finding Outdated jQuery Versions
Determining if your WordPress site is running an outdated jQuery version is relatively straightforward. There are two easy checks:
Checking Script Headers and Files
Use your browser Inspector tools and look for jQuery script tags to examine the referenced jQuery file version. Often premium themes register jQuery in the header.php file.
Using a jQuery Version Checker Plugin
Install a purpose-built plugin like “jQuery Updater” and it will detect all jQuery versions throughout your WordPress site and themes. This makes tracking down multiple versions easier.
Potential Issues When Updating jQuery
While updating outdated jQuery is advisable, keep in mind potential transition issues:
Plugin/Theme Compatibility Problems
Some plugins and themes may depend on specific legacy jQuery functionality that changed or was removed entirely in newer versions. Regressions can happen.
JavaScript Errors Breaking Functionality
Upgrading jQuery – especially major versions like 1.x to 3.x – can unintentionally cause JavaScript errors that result in broken interfaces and site issues.
Changes in How jQuery Selectors and Methods Work
The preferred usage of some selectors and methods changed between major jQuery releases. Your custom JavaScript may need refactoring for intended behavior with new jQuery.
How to Update jQuery
WordPress recommends using Google or jQuery CDN hosted versions for site performance and reliability. However, premium themes often bundle specific local copies. Here is how to update them:
Replacing Old jQuery Script References
Edit your theme files (often header.php) to call updated jQuery versions piped from Github or another CDN instead of outdated local copies.
Using wp_deregister_script and wp_register_script
Remove legacy theme bundled jQuery versions with wp_deregister_script(). Then re-register updated jQuery from a CDN with wp_register_script().
CDN Fallbacks if Self-Hosted jQuery Fails
When self-hosting jQuery, have a CDN fallback in place. If local jQuery is unavailable or errors during an update, the Google CDN will takeover gracefully.
Testing Site Functionality
After updating jQuery versions, rigorously test all site functionality using these failure points as guidelines:
Checkout, Cart, and Payment Integrations
Test ecommerce plugins to verify payments still succeed and custom cart solutions function properly post-update.
Sliders, Galleries, Forms, and Menus
Cycle through all shortcodes, widgets, and theme-specific scripts to confirm smooth functioning for slideshows, popup modals, menus dropdowns, contact forms, etc.
Browser Console for JavaScript Errors
Bring up the browser Inspector console to check if any JavaScript errors manifest while interacting with the site using the updated jQuery version.
Troubleshooting Guide
Should issues arise, here are tips for diagnosing and providing fixes:
Pinpoint Errors Related to jQuery Updates
Check browser consoles and server logs around dates of the jQuery update. Compare workflows against a backup site with original jQuery to isolate errors.
Selectively Downgrade jQuery
If you can narrow errors down to jQuery changes, selectively downgrade to an earlier version and test again as a workaround.
Getting Developer Support as Needed
For complex jQuery change-related bugs, enlist the theme developers’ help. They may need to refactor custom code to adapt to the latest jQuery quirks.
Maintaining Updated jQuery
Use these best practices to ensure sites stay updated on jQuery versions going forward:
Using Composer to Update Plugins/Themes
Manage premium themes with Composer to automate jQuery dependency updates whenever new theme versions release.
Occasional Audits for Newly Outdated jQuery
Check both sites and premium themes twice a year for potentially outdated jQuery copies creeping in and proactively update them.
