Netflix collaborated with both Google and Microsoft on creating two of the three extensions -- those already in use -- while WebCrypto was a joint effort between Google and Mozilla, the creator of Firefox.
The switch to HTML5 was not unexpected. Netflix already relies on HTML5 to stream video through its mobile apps, such as the one for iOS on the iPhone and iPad, and it's talked about shifting to the Web standard on desktops since at least 2010.
Netflix did not set a timetable for abandoning Silverlight.
Microsoft did not immediately reply to a request for comment on Netflix's decision, or to questions about Silverlight's future.
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