Are you running any security software besides MS Defender?

Thank you for responding. Yes. I have Norton and Malwarebytes. However, I have had them for YEARS ... no recent changes. And they seem to play well together. Note: the "organization" that just popped up to manage my software is "ImportEnterpriseRoots" ... to my knowledge I have had no contact with them whatsoever.

Yes, one or both apps are the reason for the manage issue. See if this helps. https://winaero.com/remove-your-browser-is-being-managed-by-your-organization-from-firefox/

By the way, ImportEnterpriseRoots is a policy that instructs Firefox to trust the Windows certificate store in addition to its own list of approved certificates. This allows your filtering software to more easily read your secure browsing to protect you from threats in pages you visit. In some cases, it may backfire if malware gets installed and modifies the Windows certificate store, so you may prefer to remove this policy.

YES !!! I stumbled my way through regedit and actually found the offending verbage and deleted it (I think). Note that my software blocked an winaero link as not secure site ... amusing, no?