Type '''about:preferences#security'''<enter> in the address box. Look under '''Logins, ''' Note: For Firefox v56+ its; '''about:preferences#privacy''' Look under '''Forms & Passwords ''' Or type '''about:logins'''<enter> in the address box. (For settings, click the 3 dots upper right) +++++++++++++++++++++++++++++++ Turn on '''Remember Logins. ''' To check the passwords you have listed, press '''Saved Logins. ''' Press the '''Exceptions''' button and see what's inside. https://support.mozilla.org/en-US/kb/password-manager-remember-delete-edit-logins

Do you mean passwords that Firefox generates automatically ? *https://support.mozilla.org/en-US/kb/how-generate-secure-password-firefox