User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9b5) Gecko/2008041514 Firefox/3.0b5 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9b5) Gecko/2008041514 Firefox/3.0b5 If proxy autoconfiguration returns multiple proxies (eg. "SOCKS localhost:2000; DIRECT"), Firefox doesn't use the latter one if the first one(s) fail to connect. This is not the behaviour that is documented in the proxy.pac docs[1] [1] http://wp.netscape.com/eng/mozilla/2.0/relnotes/demo/proxy-live.html Reproducible: Always Steps to Reproduce: 1. Configure a proxy.pac file to return two proxies, first being something that doesn't exist and the second being "DIRECT" 2. Reload the proxy.pac in browser 3. Surf the web Actual Results: Firefox can't connect Expected Results: Firefox should use the DIRECT proxy and display the site correctly I've mostly done the testing using socks proxies, but this seems to be universal for all kind of proxies in proxy.pac

related bugs: bug 366504 or bug 273258 (both unconfirmed).

I've propably missed those both when adding this, but I'm now marking this as a dupe of #366504