Please explain the problem in detail. What happens? What is/are the exact error message(s) ?

Make sure you are not blocking content.

Diagnose Firefox issues using Troubleshoot(Safe) Mode {web link}

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

https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop

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.

• Delete cookies to remove the information websites have stored on your computer {web link}

• How to clear the Firefox cache {web link}acking-protection-firefox-desktop

https://help.netflix.com/en/node/109144

"Netflix Error F7121-3078 Pardon the interruption Looks like your browser is no longer supported please install the latest version or try another browser. Error Code F7121-3078"

I made sure i have the latest Firefox browser updates installed, I tried using Troubleshoot mode and it still gives the same error. (Thanks for letting me know about that feature!) I tried clearing my cache and cookies, still doesnt work. I also turned off my tracking detection and cookie blocking, still get the same message, browser not supported.

I think https://help.netflix.com/en/node/109144 is where you ended up. Not where you wanted to go.

Websites say that Firefox is outdated or incompatible even though it's the latest version

https://support.mozilla.org/en-US/kb/how-reset-default-user-agent-firefox

You can check out at the browserspy website how websites see you:

http://browserspy.dk/browser.php

http://browserspy.dk/headers.php