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Firefox 43 - Netflix - Silverlight not recognized, not working.

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Using Windows 7 64-bit SP1. Using Firefox 43 32-bit.

After upgrading to Firefox 43 Netflix does not recognize Silverlight and forces playback in built-in HTML5 player. HTML5 player uses 90% cpu and is, therefore, unusable. Tried usual solutions: clear cache etc; uninstall, reinstall Silverlight; restart. Silverlight still not recognized or working. Tried Microsoft test site. Says Silverlight is installed and working. Tried Netflix in Internet Explorer. Siverlight is working.

I need one of two solutions: (1) working Silverlight; or (2) usable HTML5 player with moderate CPU usage.

Thank you.

Using Windows 7 64-bit SP1. Using Firefox 43 32-bit. After upgrading to Firefox 43 Netflix does not recognize Silverlight and forces playback in built-in HTML5 player. HTML5 player uses 90% cpu and is, therefore, unusable. Tried usual solutions: clear cache etc; uninstall, reinstall Silverlight; restart. Silverlight still not recognized or working. Tried Microsoft test site. Says Silverlight is installed and working. Tried Netflix in Internet Explorer. Siverlight is working. I need one of two solutions: (1) working Silverlight; or (2) usable HTML5 player with moderate CPU usage. Thank you.

Asịsa ahọpụtara

Thank you. Changing user-agent string could work, but I don't want change the headers.

Bottom line from my point of view: Silverlight cannot be used in Firefox 43 with Netflix. The change was not documented or communicated in the release notes on December 15. The blog announcements listed above were released on December 17 and only state that HTML5 playback is available, which is different from saying that Silverlight is unavailable.

My time has been wasted for stupid reasons.

Gụọ azịza a na nghọta 👍 0

All Replies (4)

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Posted to the web yesterday: https://blog.mozilla.org/blog/2015/12/17/firefox-users-can-now-watch-netflix-html5-video-on-windows/

http://techblog.netflix.com/2015/12/html5-video-is-now-supported-in-firefox.html

http://blogs.adobe.com/primetime/2015/12/netflix-html5-on-firefox/

Not sure if that is automatic and the user has no choice now to use Silverlight, so you may want to contact Netflix to see if there is a user configurable setting for your account @ Netflix.

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Thank you for the links.

I spoke with Netflix agent. Silverlight available in Firefox 42 and lower. Not available in Firefox 43 and higher. No user choice.

In [Account > Playback Settings] I switched from high data usage to low data usage. It helped but not enough. The decrease in CPU usage was mostly in the plug-in process; i.e. the Adobe Content Decryption Module. Not much decrease in the main Firefox process.

If anyone has a solution please post.

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You can try to override the user agent to show a Firefox 42 version for the Netflix website.

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Asịsa Ahọpụtara

Thank you. Changing user-agent string could work, but I don't want change the headers.

Bottom line from my point of view: Silverlight cannot be used in Firefox 43 with Netflix. The change was not documented or communicated in the release notes on December 15. The blog announcements listed above were released on December 17 and only state that HTML5 playback is available, which is different from saying that Silverlight is unavailable.

My time has been wasted for stupid reasons.