NEW Media Widgets for Images, Video, and Audio

As first introduced in the Image Widget Merge Proposal, WordPress 4.8 includes media widgets (#32417) for not only images (#39993) but also video (#39994) and audio (#39995), on top of an extensible base for introducing additional media widgets in the future, such as for galleries and playlists. To quote [40640]: The last time a new widget was introduced, Vuvuzelas were a thing, Angry Birds started taking over phones, and WordPress stopped shipping with Kubrick. Seven years and 17 releases without new widgets have been enough, time to spice up your sidebar!
Since widgets are a very old part of WordPress (since 2.2), widgets in core have been very much entirely built using PHP with some Ajax sprinkled on top. In the time since WP_Widget was introduced in 2.8, WordPress has made dramatic shifts toward developing interfaces in JavaScript, including with the Customizer in 3.4 and the Media Library in 3.5, and more recently with the focus on the REST API and the editor (Gutenberg).
Given that the media widgets are naturally interfacing with the media library JS, it is necessary that the media widgets make use of JavaScript to construct their UI instead of relying on PHP. The media widgets
Source: https://managewp.org/articles/15213/new-media-widgets-for-images-video-and-audio

source https://williechiu40.wordpress.com/2017/05/26/new-media-widgets-for-images-video-and-audio/