While I was playing around with a site, I got this error message from some google fonts I had referenced:

Mixed Content: The page at 'https://localhost:44302/Index' was loaded over HTTPS, but requested an insecure stylesheet 'http://fonts.googleapis.com/css?family=Open+Sans:400italic,400,300,600,700|Raleway:400,700|Oswald:400,700|Open+Sans+Condensed:300'. This request has been blocked; the content must be served over HTTPS.