message: enable scale
diff: @@ -15,9 +15,15 @@ const renderMathAsyncById = function(id) {
  });
  }
  -const getSvgXmlById = function (id) {
  +const getSvgXmlById = function (id, scale) {
  const svgelm = document.getElementById(id).getElementsByTagName("svg")[0];
  svgelm.setAttribute("xmlns", "http://www.w3.org/2000/svg");
  + const m0 = svgelm.getAttribute("width").match(/([\.\d]+)(\w+)/);
  + const m1 = svgelm.getAttribute("height").match(/([\.\d]+)(\w+)/);
  + const w = scale* Number(m0[1]);
  + const h = scale * Number(m1[1]);
  + svgelm.setAttribute("width", w + m0[2]);
  + svgelm.setAttribute("height", h + m1[2]);
  return svgelm.outerHTML;
  }
  @@ -79,7 +85,7 @@ window.addEventListener('message', event => {
  renderMathAsyncById("tmp00")
  .then( (tmpid) => {
  if (message.need_dataurl) {
  - const xml = getSvgXmlById(tmpid);
  + const xml = getSvgXmlById(tmpid, message.scale);
  const svgdataurl = svgToDataUrl(xml);
  document.getElementById(tmpid).style.width = "1px";
  document.getElementById(tmpid).style.height = "1px";
  