Once again, after the latest update of Firefox, i suddenly could no longer connect to the ILO interface of our HP servers. This was caused by the recent addition of 'pkix' in Firefox.
Should you see the following error while connecting to an https enabled site;
An error occurred during a connection to. Issuer certificate is invalid. (Error code: sec_error_ca_cert_invalid)
Simply disable pkix verification through: about:config - security.use_mozillapkix_verification - false