In your Question Details > More System Details on right "User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:94.0) Gecko/20100101 Firefox/94.0/I9S6ifIZ-49"

Your UA was modified by something (as the /I9S6ifIZ-49 is not normal) and some sites may be confused on what Firefox version you are using. https://support.mozilla.org/en-US/kb/how-reset-default-user-agent-firefox

I uninstalled and reinstalled Firefox and still have the same issue. Obviously somehting is wrong with Firefox, because everything works on other browsers. Perhaps its time to move on from Firefox. I can't be wasting time trying to figure out browser problems.

Did you look at the article link? https://support.mozilla.org/en-US/kb/how-reset-default-user-agent-firefox

I gave you the likely reason and how to fix your useragent.

I tried your "fix" but my user agent is correct and I still have the issue. Again I've wasted 1/2 hour of my time trying to fix a problem with your software. I'm done.

Generally speaking, Firefox uses the Widevine plugin to work with DRM (copy protected) media. The Netflix error could be a problem with using either a too-old or a too-new version of Widevine. Since Firefox normally updates Widevine automatically in the background, this problem may go away on its own, but hopefully we can get some tips on speeding that up and share them in all the new Netflix threads.

Make sure you have the latest Widevine version. You can toggle DRM off/on to see if that makes Firefox (re)load DRM components.

• Settings -> General: Play DRM
• https://support.mozilla.org/en-US/kb/enable-drm

You can possibly check the XHR requests in the Browser Console if this doesn't work.

• https://developer.mozilla.org/en-US/docs/Tools/Browser_Console