Can't login to secure website

[mozurkewich]

I have been unable to log into my account on a financial institution website. They told me that the problem was that my Mac OS was out of date. So I updated it, but I still can not log in with Firefox. No error message, the site just ignores my login attempt. Firefox is up to date. Safe mode (troubleshoot mode now) does not work either.

I can log in using Safari, but Firefox is so much better.

Any suggestions as to what is going on and how to fix it?

My OS is Big Sur, 11.6.