hi, unfortunately MS has misconfigured a security feature (OCSP stapling) on their servers which got now cached in your local firefox installation.

in order to resolve that, please enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named security.ssl.enable_ocsp_stapling. double-click it and change its value to false - this will degrade a security feature in firefox, so please revisit it in a couple of days again after microsoft has fixed their stuff and turn it back on again then...

Thank you. And apologies for making a duplicate (I did not know the original was posted).