Firefox keeps form data on reload

Just add autocomplete="off" to your inputs and you will solve the problem.

<input type="text" autocomplete="off">

jQuery to solve this on all inputs and textareas

$('input,textarea').attr('autocomplete', 'off');

Instead of going through all inputs you may also just add the attribute to your form-element like so:

<form method="post" autocomplete="off">...</form>

However the above mentioned methods on domReady did not work for me...