title: display an ajax loader icon when submitting a form
body: <p>My need is very simple. When a user try to log in and submit the login form, i would to display an ajax loader icon (like ones generated at www.ajaxload.info) in foreground with the background transparent and unclickable (like in this <a href="http://www.marmara.com" rel="noreferrer">site</a>). when the server has finished, it can display the next page or redisplay the old one with the errors.</p>
  
  <p>How can i do that?</p>
  
  <p>Thank you very much in advance.</p>