Check ssl cert trusted

sslCertTrusted.js

//Source: http://stackoverflow.com/a/25077676/1798281
<script> var sslCertTrusted = false; </script>
<script src="https://example.com/ssltest.js"></script>
<script> 
    if (!sslCertTrusted) 
    {
        alert('Sorry, you need to install the certificate first.');
        window.location('http://example.com/cert_install_instructions/');
    }
    else
    {
        // alert('Redirecting to secure connection')
        window.location('https://example.com/');
    }
<script>

ssltest.js

sslCertTrusted = true;