- jQuery 1.6.4 and jQuery UI 1.8.16. And that’s the full UI including widgets and effects. This will make it a lot easier and simpler for plugins using UI components that are not used in core as they will be able to just enqueue whatever they need.
Note: there is a known bug/regression in UI Draggable since version 1.8.13. When connecting a draggable item to a sortable container, the HTML ID of the item is removed, #17952.
- WordPress Editor API. This is an updated API for both TinyMCE and Quicktags that outputs all parts of both editors in the same way as used on the Add / Edit Post screens, #17144. Plugins will be able to use the WordPress editor anywhere including the Visual/HTML tabs and the links to upload files and show the media library.
- Quicktags refactoring. This was necessary in order to make it fully multi-instance compatible, #16695.
Note: if your plugin adds a Quicktags button please enhance it to use the new methods in quicktags.js.
- New multi-file uploader. Plupload was included as a result of Google Summer of Code project, #18206. It’s more stable and has a lot more features as well as chooses the best available interface that the current browser supports: HTML 5, Silverlight or Flash.
Note: two actions that were specific to SWFUpload were renamed and there is a new filter ‘plupload_init’ that gives access to all initialization options.
- Other enhancements: wp_enqueue_script() now works mid-page and prints the late enqueued scripts in the footer #9346, wp_localize_script() uses json_encode to properly escape and output all strings, #11520.