fiddle.css

.scr {
  width : 50px;
  height : 50px;
  border : 1px solid black;
}

fiddle.html

<div id="src" class="src" draggable="true">
  
</div>

fiddle.js

var src = document.getElementById('src');
src.addEventListener('dragstart', onDragStart, false);


function onDragStart(event) {
  event.target.addAttribute('dnd-dragged', true);
}

function onDragEnd(event) {
  event.target.removeAttribute('dnd-dragged');
}

fiddle.manifest

name: DnD
description: 
authors:
  - jsmarkus