title: How to make transparent color white instead of black in html2canvas?
body: <p>I'm trying to take a screenshot using html2canvas:  </p>
  
  <pre><code>var body = document.getElementById("body")
  $(body).html2canvas({onrendered: function( canvas ) {  
       var urlData = canvas.toDataURL("image/jpeg");  
  }});
  </code></pre>
  
  <p>My body's background is transparent, and therefore urlData because of jpeg has black background (not white like in browser).<br>
  How can I fix this behavior and make background color white in this case?</p>