I want to make a greasemonkey type script for firefox that runs before the scripts on the page. Greasemonkey scripts run after scripts on the page, so that won't work. The reason I need this is because I want to edit one of the scripts on the page. Specifically, I want to delete a script that forces the page to load inside a frame since having the page inside a frame breaks F5 (Pressing F5 makes the page jump back to the front page instead of reloading the current page). Also, I don't want to load the page through a proxy with AJAX and switching to chrome/opera is not an option either. I was thinking maybe the Jetpack add-on would work but it seems to only have the same event that greasemonkey uses, DOMContentLoaded. Any ideas?