Microsoft’s streaming video technology never matched use numbers in the marketplace against Adobe’s Flash, but it was at one point the required plug-in for watching content protected by DRM on major sites, like Amazon and Netflix. Despite this, Microsoft no longer develops it and will cease support for it. Silverlight wasn’t pre-installed on Windows 8/8.1. What happened?
Over the last few years, there’s been a move away from relying on the closed, proprietary Flash and Silverlight, and, instead, using open formats to stream video. This includes an open standard for streaming DRM-locked video, which is supported by Chrome, Firefox, Safari, and even Internet Explorer.