MediaElement upgrades in WordPress 4.9

MediaElement has been upgraded to 4.2.6 (see #39686), which includes many bugbug A bug is an error or unexpected result. Performance improvements, code optimization, and are considered enhancements, not defects. After feature freeze, only bugs are dealt with, with regressions (adverse changes from the previous version) being the highest priority. fixes as well as:

  • Removal of all dependencies to jQuery in code to makemake A collection of P2 blogs at make.wordpress.org, which are the home to a number of contributor groups, including core development (make/core, formerly "wpdevel"), the UI working group (make/ui), translators (make/polyglots), the theme reviewers (make/themes), resources for plugin authors (make/plugins), and the accessibility working group (make/accessibility). it more portable
  • Updated UIUI User interface, using flexbox
  • Improved 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) for player controls
  • Dropped support for older browsers (supports IE11+, Chrome, FF, Safari, Android 4+ and iOSiOS The operating system used on iPhones and iPads. 8+), keep in mind that ME.js applies to the front end and not just WP Adminadmin (and super admin)
  • Upgraded YouTube and Vimeo renderers to use new APIs (for Vimeo, it uses now https://player.vimeo.com/api/player.js, since Froogaloop is deprecated)
  • Added support for iOS 10 and Mac OS on websites using HTTPSHTTPS HTTPS is an acronym for Hyper Text Transfer Protocol Secure. HTTPS is the secure version of HTTP, the protocol over which data is sent between your browser and the website that you are connected to. The 'S' at the end of HTTPS stands for 'Secure'. It means all communications between your browser and the website are encrypted. This is especially helpful for protecting sensitive data like banking information.

With this upgrade, a couple of things must be considered:

  1. In order to create themes compatible with it, it is required to add the classPrefix: mejs- in the player configuration, since latest version of MEJS switched to BEM naming convention, so make sure it is set correctly.
  2. player.options.mode has been removed completely.
  3. Although jQuery was removed from the coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. package, a MediaElement migrationMigration Moving the code, database and media files for a website site from one server to another. Most typically done when changing hosting companies. file has been included to provide full backward compatibility between themes and development of new features.

A full list of changes in MediaElement.js is available in the project’s GitHub repository.

Props to @rafa8626 for helping write this Dev Notedev note Each important change in WordPress Core is documented in a developers note, (usually called dev note). Good dev notes generally include: a description of the change; the decision that led to this change a description of how developers are supposed to work with that change. Dev notes are published on Make/Core blog during the beta phase of WordPress release cycle. Publishing dev notes is particularly important when plugin/theme authors and WordPress developers need to be aware of those changes.In general, all dev notes are compiled into a Field Guide at the beginning of the release candidate phase..

#4-9, #dev-notes, #jquery, #mediaelement