Service Worker Caching, PlaybackRate and Blob URLs for Audio and Video on Chrome for Android
From version 52, Android Chrome uses the same media stack as desktop Chrome, rather than relying on the underlying platform implementation. This enables service worker media caching, variable playback rates, blob URLs on Android, MediaStream passing between APIs, and easier cross-platform debugging.
Flexbox Gets New Behavior for absolute-positioned Children
A previous version of the CSS Flexible Box Layout specification set the static position of absolute-positioned children as though they were a flex item whose size is 0px by 0px. The latest version of the spec takes them fully out of flow and sets the static position based on align and justify properties.
Performance Observer: Efficient Access to Performance Data
The W3C Performance Timeline specification defines an interface for browsers to provide programmatic access to low level timing data. This opens the door to some interesting use cases like custom performance analysis, third party tools and more.