Netflix on firefox 52

You can re-enable NPAPI support on Firefox 52 by opening about:config, adding the boolean preference plugin.load_flash_only and setting it to false.

(That's what keeps NPAPI support enabled for a few more months in Firefox ESR.)

Edit:

That preference stopped working with Firefox 54.

We have 2 Ubuntu 16.04 -computers at home and the Widevine seems to work just fine in Firefox 52 in the 64-bit version device and I can still watch Netflix and other sites that previously worked with Pipelight-plugins. However, in the 32-bit device it doesn´t, although Widevine is listed in Firefox-plugins. For a short-term solution, Gunnar Hjalmarsson´s advice worked.

I also installed Vivaldi + Widevine following these instructions: http://www.omgubuntu.co.uk/2016/07/watch-netflix-chromium-vivaldi. The correct script for 32-bit Linux is found from the comments, starting wget http://dist.control..., written by Ruari Ødegaard. I just copied the script and pasted it to the Terminal and started the installation.

Vivaldi/Widevine -solution actually worked, although the videostream looks a little bit abrupt. I don´t know if it´s because of Widevine or the laptop computer itself.

To run Netflix, Ubuntu 16.04 + Firefox 53 + Widevine plugin + VLC Media player works great, and I have had no issues running Netflix on a plain vanilla laptop. I found Netflix on Firefox did not work without VLC. I am guessing the VLC install will put the necessary video codecs on your machine. You also need to doublecheck that "Play DRM Content" is checked on Firefox (in the Preferences > Content section). I also found that Chrome 58 on Ubuntu 16.04 works fine as well. Hope this helps.

Try using Firefox ESR (Extended Support Release). It still supports plugins.

See https://www.mozilla.org/en-US/firefox/organizations/ for more information.

See https://www.mozilla.org/en-US/firefox/organizations/all/ for downloads.

Note: The Windows 64-bit version of Firefox 52 ESR only supports the Adobe Flash and Microsoft Silverlight plugins. If you also need support for Java or other plugins, choose the Windows (32-bit) download.*

*source: https://support.mozilla.org/t5/Problems-with-add-ons-plugins-or/Why-do-Java-Silverlight-Adobe-Acrobat-and-other-plugins-no/ta-p/31069