Connection to website error in Firefox browser

An error occurred during a connection to www.__________. Invalid OCSP signing certificate in OCSP response. Error code: SEC_ERROR_OCSP_INVALID_SIGNING_CERT

OCSP is a method to check whether a site's SSL certificate has been revoked by its issuer. "Stapling" is a method for the site to deliver proof of validity along with its own certificate. This improves privacy for the user because you don't need to reveal to a third party (the issuer) that you need to know about the site you're trying to use.

Solution:

As a temporary workaround, you can disable OCSP stapling. With that change, instead of Firefox expecting sites to provide an OCSP certificate -- a verification that its certificate has not been revoked -- Firefox will query the service provider that signed the certificate. This is good for security but not the best arrangement for privacy, because the service provider knows a computer at your IP address is checking out that site. So after you finish using the site, you can switch the setting back.

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful or accepting the risk.

(2) In the search box above the list, type or paste ocsp and pause while the list is filtered.

(3) Double-click the security.ssl.enable_ocsp_stapling preference to switch the value from true to false.