firefox - In Firebug, how can I stop a redirect?

In Firebug, how can I stop a redirect? I want to examine and edit a webpage before it redirects. Under the Net tab, using Persist I can see all the GET including the previous pages and the redirect page, but I am still taken to the final redirect page. I want to stop one move before this. Is it possible?

EDIT: It is a JavaScript based redirect, but I need the rest of the JavaScript working, so blocking all JavaScript from execution is not a solution in this instance.