I'm writing a rudimentary screen scraper tool as an FF add-on (using DOM and xpaths). Currently, it runs fine. However, it also runs very slowly, as Firefox takes some time to request and download all the non-textual elements on each page (simply writing a separate application that parses the raw HTML is not feasible as some of the pages that need scraping make rather complicated AJAX requests). While I have seen 'Image block' and 'Flash block' plugins, these all seem to merely prevent the images/flash from displaying, rather than actually suppressing the GET requests.
So my question is this: is there any way for me to prevent Firefox from issuing these GET requests to begin with?