How can I debug a Firefox extension with Firebug?

Question

I\'m trying to use Firebug to debug a JavaScript file in an extension I\'ve added to Fx 4.
Can anyone tell me how to do it? I can only see website scripts.

Answer 1

Please see MDN - Building An Extension - Debugging Extensions, which shows what tools Firefox provides you with to natively debug extension, also take a look at Dive Into Greasemonkey - Debugging User Scripts (PDF, p.13) which is aimed more specifically at your request.

Other than that, see How to debug a Greasemonkey script with the Firebug extension?