jQuery, the pioneering JavaScript library that revolutionized web development, has released jQuery 4, marking its first major version in almost 10 years. The release coincides with the library’s 20th anniversary, having first been introduced on January 14, 2006.
jQuery 4 brings extensive modernizations while maintaining the simplicity and developer experience. The team has focused on trimming legacy code, removing deprecated APIs, and dropping support for outdated browsers, resulting in a leaner and more performant library. The jQuery team expects most users will be able to upgrade with minimal changes to their code, supported by a comprehensive upgrade guide and jQuery Migrate plugin.
A key support change in jQuery 4 is the removal of support for Internet Explorer 10 and older browsers, including Edge Legacy, iOS versions earlier than the last 3, and Android Browser. Internet Explorer 11 remains supported in this release, though the team has indicated that support will be removed in jQuery 5.0.
The library source code has been migrated from AMD to ES modules, making jQuery compatible with modern build tools and development workflows. Developers can now import jQuery directly as ES modules through the use of script type equals module tags, and the project has switched from RequireJS to Rollup for packaging.
The modernizations have been well received by the community, with users on Reddit noting how far vanilla JavaScript has become:
I think it’s a sign of how good vanilla browser JS is when half of the changelog is stuff getting removed.
jQuery 4.0 adds support for Trusted Types, ensuring that HTML wrapped in TrustedHTML can be used as input to jQuery manipulation methods without violating Content Security Policy directives. The library has also switched most asynchronous script requests to use script tags rather than inline scripts to avoid CSP errors.
Several deprecated functions have been removed, including jQuery.isArray, jQuery.parseJSON, jQuery.trim, and jQuery.now, as modern browsers now provide native equivalents like Array.isArray(), JSON.parse(), String.prototype.trim(), and Date.now(). Removing deprecated APIs has saved over 3,000 bytes of gzipped code.
The slim build has been further reduced to around 19.5k bytes gzipped by removing Deferreds and Callbacks, as native Promises are now available across all supported browsers except IE11.
Community reaction has been positive, with HackerNews users highlighting that jQuery’s code remains “shorter, cleaner, and more intuitive than the vanilla modern JS” alternatives.
On a reddit thread for the release, which attracted over 130 replies, one person asked:
Real question: why use this on any greenfield app?
With one replier suggesting:
I’m guessing probably habit and convention more than anything. It’s still bundled with WordPress and all the tutorials use it.
Another commenter said the following, which emphasises the library’s stability and predictability in an ecosystem of rapidly changing frameworks:
Most people don’t use it on a greenfield app, but why does that matter?
It’s still downloaded by millions everyday so I suspect there are some good reasons why people still use it today.
- Maintaining or extending a large existing codebase that uses Jquery,
- Extremely fast DOM work with minimal mental overhead
- Cross browser normalization still has value
- Small interactive behavior without a framework
- Massive plugin ecosystem that still works
- Excellent readability for non specialists
- Progressive enhancement and server rendered sites
- Performance is no longer the liability it once was
- Reduced dependency surface
- It is boring and boring can be good
Compared to modern alternatives like vanilla JavaScript DOM APIs or frameworks such as React and Vue, jQuery continues to excel in scenarios involving progressive enhancement, server rendered sites, and small interactive behaviors without the overhead of a full framework. The library remains a practical choice for maintaining existing codebases and projects where simplicity and cross browser normalization are priorities.
jQuery is available on the jQuery CDN and via npm with npm install [email protected]. The release represents not just a technical milestone but a celebration of 20 years of making web development more accessible and enjoyable for millions of developers worldwide.
