The experts in another Forum Always suggest / Ask IF you'll Try Help / Troubleshoot mode (FF Safe Mode). IF THAT works then some Addon or special Setting is causing the issue and it's Trial & Error to determine what it is. I also created and have a Desktop Shtcut to a 2nd - Test- Profile to measure if Same Problem exists with it. On rare occasions something Fails with Troubleshoot mode BUT succeeds with the Different Profile. That fact helps experts Or tells you to re-build from that new Profile.

Hello! You can try disabling the Enhanced Tracking Protection

To do this:

• Go to the website that you're having issues with;
• Click the Shield Icon in the left of the address bar;
• Click the toggle button next to "Enhanced Tracking Protection is ON for this site";
• Check if the issue was fixed.

Seemed like a good possibility, but it didn't work. Thanks anyway!

I tried FF troubleshoot mode and it didn't work either. Thanks for the info though.

It just seems weird that I can log in with my Firefox app on my phone, but not on either of my computers.

Hello again! You can report website compatibility issues with Firefox by filling out this form: Webcompat Form

It's odd that it is happening on two computers (unless you have them 'synced'). Try clearing the cache and, if that doesn't help, clear cookies and site data. I have added a link relating to basic troubleshooting.

https://support.mozilla.org/en-US/kb/how-clear-firefox-cache https://support.mozilla.org/en-US/kb/delete-cookies-remove-info-websites-stored https://support.mozilla.org/en-US/kb/troubleshoot-and-diagnose-firefox-problems

Clearing the cache did the trick! Thanks terry21 and everyone who helped!