The warnings will become less and less as time passes as more and more sites will migrate to HTTPS. The warnings may raise awareness, and that is definitely a good thing. If you set it to true, Firefox will auto-fill form pages on HTTP pages as well.
The default value of false prevents the Firefox web browser from filling out form information on HTTP pages. You need to modify another preference of the Firefox web browser for that. After using Firefox for years, suddenly I repeatedly get the message that 'this connection is untrusted' for many sites, even including In the details it says: 'The certificate is not trusted because no issuer chain was provided.' I have tried everything I read in the Mozilla help forums, but nothing has worked. So for now i will use this, but either its firefoxs fault or Sophos XG bug. Version 53.02 doesnt even give an option to add an exception.
so that i can atleast open and use gmail and youtube and other https related websites. Toggling the preference won't have any effect on the automatic filling out of forms on HTTP pages. I just installed version 51.0.1 and it still shows an insecure connection but atleast this version lets me add an exception. If you set it to false, those warnings are not shown. The default value of the preference is true, which means that the feature is enabled and that Firefox will display warning prompts when you activate insecure login fields.
