User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; 9LA; .NET CLR 1.0.3705; .NET CLR 1.1.4322; .NET CLR 2.0.50727; 9LA; 9LA) Build Identifier: Mozilla/5.0 (Windows NT 5.1; rv:2.0b6pre) Gecko/20100906 Firefox/4.0b6pre At RBC, I've been using Firefox (including 4b4) successfully via our proxy. Firefox 4b5 introduces new mechanism to connect to https sites directly, but this does not appear to work via the proxy. Confirmed with latest Minefield. All https access via proxy are all broken. Local https connections work fine. 3 scenarios that demonstrate problem: 1) https://www.ebay.ca, select "Sign In". No connection to sign-in page. 2) Attempt to open link to https in new tab. Get empty new tab. 3) Updates are broken - which is going to be a real pain for some users. - Help/Check for Update returns "Update XML file malformed (200)" - Should either say "No update available" or provide update info/install panel Reproducible: Always Steps to Reproduce: 1.http://www.ebay.ca 2.Select the "Sign In" button 3.Wait for https connection to sign-in... that never arrives. Actual Results: No connection to https via proxy. Direct connection works. Update also broken - Result is no https outside our firewall. Expected Results: Expect all https connections to be established (whether direct or via proxy). Expect updates to work, so next beta gets successfully loaded. New https feature appears to have not been tested with proxy, an oversight.

If it works with these Builds http://ftp.mozilla.org/pub/mozilla.org/firefox/tryserver-builds/sstamm@mozilla.com-ad3eaca19f44/tryserver-win32/ it's a Dupe of Bug 592197 what will be included in Beta 6.