From MozillaZine Knowledge Base
This preference was one of several added to allow low-level tweaking of the HTTP networking code. After a portion of the same code was significantly rewritten in 2001, the preference ceased to have any effect (as noted in all.js as early as September 2001).
Currently, the timeout is determined by the system-level connection establishment timeout. Adding a way to configure this value is considered low-priority.
Possible values and their effects
This integer preference specified the number of seconds to wait after firing off an HTTP request before considering it “timed out”. It was originally set to 30 by default. This preference no longer has an effect.
First checked in
Has an effect in