message: tweak: use a temp variable for smaller size.
diff: @@ -460,10 +460,11 @@ class SVGPainter implements PainterBase {
  toDataURL() {
  this.refresh();
  - const outerHTML = this._svgDom.outerHTML
  + const svgDom = this._svgDom;
  + const outerHTML = svgDom.outerHTML
  // outerHTML of `svg` tag is not supported in IE, use `parentNode.innerHTML` instead
  // PENDING: Or use `new XMLSerializer().serializeToString(svg)`?
  - || (this._svgDom.parentNode && this._svgDom.parentNode as HTMLElement).innerHTML;
  + || (svgDom.parentNode && svgDom.parentNode as HTMLElement).innerHTML;
  const html = encodeURIComponent(
  outerHTML
  .replace(/></g, '>\n\r<')
  