How can I check if any of my Firefox extensions or plugins are using the internet?

Question

Is there a way to monitor if Firefox extensions or plugins are using the internet?

Answer 1

I'm fairly sure Firebug can track extension XHRs in its NET tab. You could also use a packet inspector such as Wireshark to see what traffic is generally going out of your system.

Failing that most extensions aren't that big. You can always just grep them.