Type "about:config" in the address bar. Double click on the following to set (help yourself with "filter" to get the keys quicker):
network.http.max-connections : 64 network.http.max-connections-per-server : 21 network.http.max-persistent-connections-per-server : 8 network.http.pipelining : true network.http.pipelining.maxrequests : 100 network.http.proxy.pipelining : true
Of course it also works under Windows.
