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FF 34.05 Cannot watch Netflix or streaming sports recently and don't know where the incompatibilty lies

  • 3 cavab
  • 1 has this problem
  • 16 views
  • Last reply by cor-el

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Running Mac OSX 10.7.5 on MacBook Prol Since this FF release (and possibly one earlier) I have been unable to watch on Netflix and noticed the same problem when trying to watch Sunday Night Football (streaming.nbcsports). I closed FF and tried with Safari. Safari prompts me to download Silverlight upgrade each time I switch over to it to watch Netflix or SNF. In any event, I tried to find help on the different Mozilla forum and found that when I closed FF, and reopened in Safe Mode, Netflix now works. (It's Tuesday so I'm without football!) I think that I had two FF extensions for blocking those pesky audio and video ads (not sure which ones as I'm in Safe Mode now). But they were both Mozilla downloads.

Question is: Can I only watch Netflix in Safe Mode on Firefox? Or is there some setting(s) to allow me to have both adblock et al, running while I watch streaming video on Netflix?

I hope this is clear as I am a non-technical guy and am unsure if I'm providing correct information or not enough.

Thank you for any assistance/guidance.

Keynes66

Running Mac OSX 10.7.5 on MacBook Prol Since this FF release (and possibly one earlier) I have been unable to watch on Netflix and noticed the same problem when trying to watch Sunday Night Football (streaming.nbcsports). I closed FF and tried with Safari. Safari prompts me to download Silverlight upgrade each time I switch over to it to watch Netflix or SNF. In any event, I tried to find help on the different Mozilla forum and found that when I closed FF, and reopened in Safe Mode, Netflix now works. (It's Tuesday so I'm without football!) I think that I had two FF extensions for blocking those pesky audio and video ads (not sure which ones as I'm in Safe Mode now). But they were both Mozilla downloads. Question is: Can I only watch Netflix in Safe Mode on Firefox? Or is there some setting(s) to allow me to have both adblock et al, running while I watch streaming video on Netflix? I hope this is clear as I am a non-technical guy and am unsure if I'm providing correct information or not enough. Thank you for any assistance/guidance. Keynes66

All Replies (3)

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That is a problem with Silverlight.

  • bug 1109484 - Silverlight fails to run on Netflix and Amazon Instant Video with Dec 9 update
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Thank you for the info. Uninstall/reinstall did not solve problem. And...Amazon IV does not play (I had used Safari last night and forgot)

If it were Silverlight issue, why can I get Netflix in FF safe mode...but not with plugins/extensions enabled? Why would Safari allow Netflix to play if using same Silverlight package? ( Or, I assume it is using same package?)

Modified by Keynes66

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

If it works in Safe Mode and in normal mode with all extensions (Firefox/Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via "Firefox > Exit" (Windows: Firefox/File > Exit; Mac: Firefox > Quit Firefox; Linux: Firefox/File > Quit)


In Firefox Safe mode these changes are effective:

  • all extensions are disabled (about:addons)
  • default theme is used (no persona)
  • userChrome.css and userContent.css are ignored (chrome folder in profile folder)
  • default toolbar layout is used
  • JavaScript JIT compilers are disabled
  • hardware acceleration is disabled (Options > Advanced > General)
  • plugins are not affected
  • preferences are not affected

Modified by cor-el