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Firefox 89.0.2 & Netflix

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  • 1 has this problem
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  • Last reply by FredMcD

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I was watching Netflix easely on my iMac macOS Big Sur 11.4 using Firefox 89.0.2 since few month , but suddenly, since few day, it's not possible anymore to watch any movies or series, I got an ERROR Code F7121-1331. Netflix says that I must change browser (like Chrome, Gmail etc... indeed, if I use Safari to get connected, Netflix works perectly) They have no others solutions to offer ! I do hope Firefox can do much better then Netflix ! Please...

I was watching Netflix easely on my iMac macOS Big Sur 11.4 using Firefox 89.0.2 since few month , but suddenly, since few day, it's not possible anymore to watch any movies or series, I got an ERROR Code F7121-1331. Netflix says that I must change browser (like Chrome, Gmail etc... indeed, if I use Safari to get connected, Netflix works perectly) They have no others solutions to offer ! I do hope Firefox can do much better then Netflix ! Please...
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Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

If there is still a problem,

Start Firefox using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh). Is the problem still there?

While you are in Troubleshoot(Safe) mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}