Firefox>Preferences>Security space.

You're in the right spot.

What happens if you un-check 'Use a master password'?

https://support.mozilla.org/en-US/kb/use-master-password-protect-stored-logins#w_removing-the-master-password

It is possible that there is a problem with the key3.db and signons.sqlite files that store the encrypted names and passwords in Firefox. Rename the key3.db and signons.sqlite files in the Firefox profile folder. You can add .old to the file names (key3.db.old and signons.sqlite.old) or move them to another folder to make it possible to undo the action. You need to set a new Master Password after renaming or deleting key3.db and all currently saved passwords are lost. If that has worked then you can remove the renamed files that are no longer needed. Otherwise you can rename the files to their previous names (signons.sqlite and key3.db

You can use this button to go to the currently used Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)

When I ask to Remove password,

I enter the Master password, but,

the "Remove" button is grayed out.

OK, did all that. Renamed both files w/ .old suffixes

went to Firefox>Preferences>Security and the same issue of a grayed out "Remove" button exists.

Does not want to allow remove master password.

Is there a Master Password set?

Do you get asked for the MP when you click "Saved Passwords" and "Show Passwords"?

• Firefox > Preferences > Security: Passwords