User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9) Gecko/2008052906 Firefox/3.0 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9) Gecko/2008052906 Firefox/3.0 While using firefox 3 i am unable to visit an https website through a local proxy like WebScarab or Burp Suite. It seems that the error comes from the fact that both these proxies create their own certificates where the domain name does not match the site that i am accessing. Below is the following error: The certificate is not trusted because it is self signed. The certificate is only valid for <a id="cert_domain_link" title="PortSwigger">PortSwigger</a> (Error code: sec_error_untrusted_issuer) I regularly uses these tools to perform my job. I am a security analyst. In previous releases of firefox i did not have these issues. Is there a way to disable certificate validation on the client for an advanced user or a way to always accept certificates from these tools or others. I'm stuck using IE and Opera for now. Reproducible: Always Steps to Reproduce: 1. open Burp suite 2. change proxy settings to localhost:8080 3. navigate to any https site Actual Results: alert box stating the following. The certificate is not trusted because it is self signed. The certificate is only valid for <a id="cert_domain_link" title="PortSwigger">PortSwigger</a> (Error code: sec_error_untrusted_issuer) Expected Results: pop up asking if i want to continue.