This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox 89.0.2 & Netflix

  • 1 reply
  • 1 has this problem
  • 3 views
  • Last reply by FredMcD

more options

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...
Attached screenshots

All Replies (1)

more options

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}