Mixed Content: The page at 'https://www.test.com/signup.aspx' was loaded over HTTPS, but requested an insecure script 'http://api.Test.com/testform.js?field=Test'. This request has been blocked; the content must be served over HTTPS.
Error screen shot below
to solve the error by adding this code to your html file:
script.src = ("https:" == document.location.protocol ? 'https' : 'http') + ":///api.Test.com/testform.js?field=Test?