Comment 221 for bug 113201

The most immediate problem is that nsCrossSiteListenerProxy::OnChannelRedirect is broken: it never allows the redirect, because it calls CheckRequestApproved which always fails on channels that are not 2xx HTTP responses (which no channel being redirected ever is).

Sicking says fixing that won't be enough because preflight requests (for POST/PUT) aren't allowed to be redirected right now; we'd need to fix that to allow the PAC redirect for those.