Chrome Version       : Version 49.0.2623.75 (64-bit) Linux Mint 17.3
URLs (if applicable) :
Other browsers tested: Firefox
  Add OK or FAIL, along with the version, after other browsers where you
have tested this issue:
     Safari: Not tested
    Firefox: OK 49.0.2
         IE: Not tested

What steps will reproduce the problem?
(1) Well, this is probably not so simply to reproduce with a smaller code snippet :(
    Will provide a code snippet under additional info below.
(2)
(3)

What is the expected result?
An SVG image is being converted to PNG and being rendered in the 
summernote editor.


What happens instead?
Chrome renders just a blank image (due to shorter base64 string ?)

Please provide any additional information below. Attach a screenshot if
possible.

Basically i am trying to render html to an svg or png image. I decided to do this in 2 steps, first embedding the html into svg and converting to png afterwards.
Because i want to create non-editable images with a text on it inside the summernote editor, i cant embed the SVG directly... summernote will let me edit inside the "image" then...
So here a snippet from my code.
Furthermore when examining the base64 result strings, the chrome ones are much shorter than the firefox ones... Why is this ? is the image not drawn properly prior to doing canvas.toDataURL() or is there some issue with toDataURL() itself ?

var data = '<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"'+width+'\" height=\"'+height+'\">' + 
       //  '<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"100%\" height=\"100%\">' + 
           '<switch>' + 
           '<foreignObject width=\"100%\" height=\"100%\" requiredExtensions=\"http://www.w3.org/1999/xhtml\">' +
           '<div xmlns=\"http://www.w3.org/1999/xhtml\">' +  
              '<span style=\"$style\">My Span</span>' +
           '</div>' +
           '</foreignObject>' +
           '<text x=\"0\" y=\"0\">Your SVG viewer cannot display html.</text>' +
           '</switch>' + 
           '</svg>';

                
           var blob = new Blob([data], {type: 'image/svg+xml;charset=utf-8'});
           //attempt to convert to png here... 
           //because Htmlpurifier didnt let the img pass... :)
           canv = document.createElement('canvas');
           canv.width = width;
           canv.height = height;
           ctx = canv.getContext('2d');
           img2 = new Image();
           img2.crossOrigin='Anonymous';

           var reader = new window.FileReader();
           reader.onloadend = function () {
              img2.onload = function() {
              ctx.globalAlpha = 1.0;
              ctx.drawImage(img2, 0, 0);

              var img = new Image();
              img.crossOrigin='Anonymous';
                               
              img.onload = function() {
                 //insert img to summernote editor here
              }
                               
              img.src = canv.toDataURL('image/png;charset=utf-8'); 
              // should be base64...      
              img.alt = 'alternative value'
              img.setAttribute('class', 'myclass');
          };
                            
          img2.crossOrigin='Anonymous';
          img2.src = reader.result;
                        
          reader.readAsDataURL(blob);