I am looking for an extension for Firefox that will list all JavaScript variables on a page, along with their values, and will allow you to edit them so that their values are different. If there is a way to do this, whether it be with or without an add-on, please tell me so.
Thanks for helping me out!
You can try firebug, it is a very nice tool, you can debug the javascript and output all the variables in scope.
https://addons.mozilla.org/en-us/firefox/addon/firebug/
https://getfirebug.com/downloads