anchor.diff:  require = require_save;
   requirejs = requirejs_save;
   define = define_save;
  -function ifsharpMakeImage(gd) {
  -    var fmt =
  -        (document.documentMode || /Edge/.test(navigator.userAgent)) ?
  -            'svg' : 'png'
  +function ifsharpMakeImage(gd, fmt) {
       return Plotly.toImage(gd, {format: fmt})
           .then(function(url) {
               var img = document.createElement('img');
  
positive.code:             div.appendChild(img);
              gd.parentNode.replaceChild(div, gd);
          });
  }
  </script>
  """
  
negative.code:             .Replace("Plotly.newPlot(", "Plotly.plot(")
              .Replace(
                  "data, layout);",
                  "data, layout).then(ifsharpMakePng);")
  
      member __.GetSvgHtml() =
          let html = __.GetInlineHtml()
          html
              .Replace("Plotly.newPlot(", "Plotly.plot(")
              .Replace(
                  "data, layout);",
                  "data, layout).then(ifsharpMakeSvg);")
  
  type XPlot.Plotly.Chart with
  
      static member Png (chart: PlotlyChart) =
          { ContentType = "text/html"
            Data = chart.GetPngHtml()
          }
  
      static member Svg (chart: PlotlyChart) =
          { ContentType = "text/html"
            Data = chart.GetSvgHtml()
          }
  