https://support.mozilla.org/en-US/kb/insecure-password-warning-firefox There is a hidden preference to turn off the warning on the login form if it really annoys you and you think it will never be of value. Here's how: Type '''about:config'''<enter> in the address bar. If a warning screen comes up, press the '''I Accept the Risk''' button. At the top of the screen is a search bar. Set; '''security.insecure_field_warning.contextual.enabled''' = False '''security.insecure_password.ui.enabled''' = False