1 Introduction

This document describes the level of support provided by Microsoft web browsers for the W3C Media Source Extensions specification [W3C-MEDIA-SOURCE], published 17 November 2016. The [W3C-MEDIA-SOURCE] specification extends HTMLMediaElement ([W3C-HTML51]) to allow JavaScript to generate media streams for playback. Allowing JavaScript to generate streams facilitates a variety of use cases like adaptive streaming and time shifting live streams.