When you sent data over a form, you can see what exactly you sent if you see the logs on the Firebug console. It also gives you an option to resend the data. Is there is a way to edit that data within Firebug to send something different? If not, I would like to know if there is any other tool that can.
This is an example of what I see on Firebug console after having sent a certain form:
Params Headers Post Response JSON Parameters application/x-www-form-urlencoded Do not sort [action] save [user name] Someuser [Source] action=save&username=Someuser