WordPress 4.2 Field Notes

WordPress 4.2 includes both new and improved features. It also includes changes under the hood.  While I’m sure you’ve been testing your themes, plugins, and sites in preparation for the release, you may have missed the announcements of all the changes. Here is a quick rundown of developer related things you should know:

• The new wp.a11y.speak() APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways. is available. When a change on the page happens, you can make sure that screen reader users are notified with this helper.
• The default admin color scheme has been tweaked. Minor, but if you use the WordPress colors directly in your code, you should update the code.
• When possible, WordPress now will use utf8mb4 as the database character set. This change has to the ability to store Emoji, which has lead to a couple of changes to help display emoji on all 💻 and📱.
• Work along the Taxonomy Roadmap continued with terms being split when one of the terms is updated.  If you are storing term IDs in places such as post metaMeta Meta is a term that refers to the inside workings of a group. For us, this is the team that works on internal WordPress sites like WordCamp Central and Make WordPress., user meta, or options, then it’s likely you’ll need to update your code to prevent problems when a shared term gets split.
• The default output of comments_popup_link now uses the.screen-reader-text class. The accessibilityAccessibility Accessibility (commonly shortened to a11y) refers to the design of products, devices, services, or environments for people with disabilities. The concept of accessible design ensures both “direct access” (i.e. unassisted) and “indirect access” meaning compatibility with a person’s assistive technology (for example, computer screen readers). (https://en.wikipedia.org/wiki/Accessibility) team has put together a post on hiding text for screen readers that includes sample code to use in your themes.
• order_by and meta_query now have a syntax that makes complex queries for WP_Query, WP_User_Query, and WP_Comment_Query easier.
• The experimental TinyMCE views API has continued to evolve. As this is an experimental API, use in production is not recommended unless you closely follow the development as breaking changes are possible.
• Two UIUI User interface components used by coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress., spinners and admin notices, have been improved. The change to spinners is a change to how they are added and the change to adminadmin (and super admin) notices is the ability to optionally make them dismissible.

Additionally, the bundled version of jQuery UI has been upgraded from 1.11.2 to 1.11.4 and jQuery to 1.11.2.  The team also fixed 231 defects reported againgst previous versions of WordPress.  Please continue testing in preparation for the imminent 4.2.0.   WordPress wouldn’t be where it is without you.

UPDATE: Add information on spinners and admin notices.

#4-2, #dev-notes, #field-guide