<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" onload="boom();">

<script>

function boom()
{
  document.getElementById("thhh").setAttributeNS("http://www.w3.org/1999/xlink", 'href', '');
}

</script>

	<defs>
    <g id="ch" style="counter-reset: c;">
      <rect x="75" y="0" width="75" height="75" fill="lightgreen" style="counter-increment: c;"/>
    </g>
    
  </defs>

  <use id="thhh" x="0" y="0"><use xlink:href="#ch" x="0" y="0"/></use>

</svg>