code: function hasMathMLSupport() {
    var div = document.createElement("div"), box;
    div.innerHTML = "<math><mspace height='23px' width='77px'/></math>";
    document.body.appendChild(div);
    box = div.firstChild.firstChild.getBoundingClientRect();
    document.body.removeChild(div);
    return Math.abs(box.height - 23) <= 1  && Math.abs(box.width - 77) <= 1;
  }
docs: **************************************
  Until now (february 2016), only Firefox and Safari support MathML.
  
  this polyfill  detects the  lack of MathML  support and  transform every
  MathML tag in some thing that vagueley looks like real MathML.
  **************************************