We work hard to keep our external libraries as up-to-date as possible with each major release A release, identified by the first two numbers (3.6), which is the focus of a full release cycle and feature development. WordPress uses decimaling count for major release versions, so 2.8, 2.9, 3.0, and 3.1 are sequential and comparable in scope.. Here’s what you can find today in trunk A directory in Subversion containing the latest development code in preparation for the next major release cycle. If you are running "trunk", then you are on the latest revision., all of which are the latest version:
Edit: jQuery 1.8.1 (due out this week) and jQuery UI User interface 1.9 (due out next week) are now both in trunk.
And, Backbone.js 0.9.2 and Underscore.js 1.3.3 were both added to core last week.
If you’re a plugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party developer using a bundled library, we strongly suggest you follow their development as well, to ensure code you write will be compatible in the future. The projects we have adopted have very similar backwards compatibility policies as ours (which would be strive to always be compatible), which make this pretty easy to do.
Additionally, Prototype and script.aculo.us have been removed from core Core is the set of software required to run WordPress. The Core Development Team builds WordPress.. They are still registered; enqueueing them will pull from ajax.googleapis.com. This is only being done for backwards compatibility and doesn’t indicate a change in policy. It was just a lot of bloat to keep shipping when core hasn’t used either for four years. (Both were updated to the latest versions in the process, something we can/may continue to do.)
See also the conversion to .min.js from .dev.js.