Forum Discussion
Dangerous exclamation in triangle filled in icon on every page at the beginning right before loading
I know! An update set #enable-mark-http-as in the flags to Enabled (mark with a grey triangle icon) from Disabled.
I don't think it should have a grey triangle or be actively dangerous. I think an 'i' in an outlined circle is sufficient. FYI setting it to Enabled, Default and Disabled all set it to Enabled (mark with a Not Secure warning and dangerous on form edits). I still set it to disabled to tell Microsoft and Google (I also use Chrome). I support making HTTPS less prominent though.
Okay so based on what you say, If all of the websites are shown as insecure, the first logical thing that comes to mind is that the Trusted Root Certificate Authorities are probably missing/deleted.
https://www.thewindowsclub.com/manage-trusted-root-certificates-windows
Though it could also be a 3rd party extension or Flags. so you could try resetting all the flags to their default values and temporary disabling any 3rd party extension.