Disable disable Firefox insecure password warnings
Firefox 52.0 Release (on March 7, 2017) added user warnings for non-secure HTTP pages with logins, now displaying a "This connection is not secure" message when users click into the username and password fields on pages that don’t use HTTPS.
Here’s how to disable Firefox insecure password warnings:
- Open a new tab, paste about:config into the address bar and hit enter.
- If you see the "This Might Void Your Warranty" page, click the blue "I accept the risk!" button. Understand we are manually modifying Firefox’s default settings.
- In the Search box at the top, paste insecure_field_warning.contextual.enabled
- Double click the setting to change it to "false", to disable Firefox’s insecure password warning.
- Done! Now when you visit pages with HTTP login forms, the warning will no longer appear.
If you also want to restore autofill functionality, so that your saved login/password automatically populates in an HTTP form, keep the configuration page open and follow the next step.
Optional: In the Search Box on the about:config page, paste signon.autofillForms.http, double click the setting to change it to "true", this will enable autofill.
Sources:
https://www.mozilla.org/en-US/firefox/52.0/releasenotes/
https://blog.mozilla.org/security/2017/01/20/communicating-the-dangers-of-non-secure-http/
https://www.thesslstore.com/blog/disable-firefox-insecure-password-warnings/