title: Trigger JavaScript event when using Google auto fill on Firefox
body: <p>I have a form, in which I am disabling the submit button until an user has typed in all the mandatory fields. I was initially using <code>onkeyup</code> to keep a tab on the mandatory fields and enable the button when all the mandatory fields are filled.</p>
  <p>But I had users complaining that they filled in the form using AutoFill button on the Google toolbar and the submit button was still disabled.</p>
  <p>I fixed this problem in IE by calling the <code>onpropertychange</code> event for each input element and it worked nicely.</p>
  <p>But in Firefox, I couldn't find an event which will get triggered when the Google autofill button is clicked.</p>
  <p>Help much appreciated.</p>