Can't identify Facebook?

[TheUSMC2017]

I don't know if this has already been posted, or if it's just me but my account is linked to facebook, and every time I go to a new page on Bladeforums, I get this message.

The certificate for this website is invalid. You might be connecting to a website that is pretending to be 'www.facebook.com' which could put your confidential information at risk. Would you like to trust the website anyway?

 

[Nordic Viking]

Your webbrowser (Safari) does not recognise Digicert as a certificate authority.

The quick workaround would be to click on the trust www.facebook.com checkbox until you figure out how to install the cert authority onto your Mac.