Some websites modify the login form when you submit the form and copy the actual values to hidden fields. If Firefox notices a change in the login field (i.e. the submitted password doesn't match the saved password) then Firefox shows a dialog to update the stored username/password. In such a case you can create a login block exception to suppress this update dialog.

If Firefox notices that the content of the password field has changed then Firefox may want to update the stored password although Firefox would ask for confirmation (you might have missed to request). In such a case best is to create a login block exception for this origin (protocol and hostname) to prevent Firefox from updating the stored password. If necessary you can edit the password in the Firefox Password Manager (about:logins).

• https://support.mozilla.org/en-US/search/?product=firefox&w=2&q=%22login%20block%20exception%22

Are you suggesting that I modified my password to this ridiculous string of characters? That did not happen. This is stored in my Firefox password manager and I did not alter it. Is there a log file that I can view it will show who and when and where my password was changed?

Where did this very very long password come from because it did not come from me and how did it get into my settings in Firefox and where's the log file entries that shows me who what when and where put this entry into my Firefox browser ????