Have you tried to enable(disable) OCSPValidateCertificates for certain web-sites via override.ini ?
I did 
and it works! Some site stopped working for me last week, throwing an error
'Secure connection: critical error (1066)'
and after adding the following line to a dedicated section in override.ini - I can access that site over https again:
SecurityPrefs|OCSP Validate Certificates=0