I found that the behavior of Firefox on proxy server side is quite different from what I expected.
I thought that you can bypass local traffic by putting local address range, such as 192.168. But I discovered that it is not enough, you have to put DNS names of the server also.
Say that I have a local server testwww. If I don't out testwww into the bypass list, the traffic will go through proxy server.
Is this by design?