The SSL/TLS certificate fingerprint is a security feature of the website certificate that cannot be spoofed by a MITM attack. You can be certain of a website certificate's authenticity by comparing the fingerprint of the certificate your browser sees, with the one grc.com's server sees. This verification is crucial if you are using a system of cert/domain pinning. Learn more about this at https://www.grc.com/fingerprints.htm Prior to Steve Gibson setting up the service at the above website the certificate fingerprint was standard https information that could be viewed in any web browser. Can you still view the SSL/TLS certificate fingerprint in yours?