title: How to detect date format defined by browser?
body: <p>I'm using HTML5 input type=date field and because some browsers still don't support this feature, I would like to create error validation message for browsers that display just normal text field instead of date field. This error message should look like </p>
  
  <blockquote>
    <p>Please enter date in format: ...</p>
  </blockquote>
  
  <p>But I need to find the correct format, that the browser is set to. Is there any php/js/jQuery way how to find out this?</p>