title: Putting Facebook photos on canvas, taint canvas when trying to send it toDataURL. Can I set Facebook's header for CORS?
body: <p>I am adding facebook photos to a Konva canvas (more or less identical to a HTML5 canvas) and when I try to export the canvas using toDataURL I am given a warning stating the canvas is tainted (specific error below). I know this has to do with trying to export a photo with a different origin than the server but I am curious if I can set the Facebook header to allow cross origins? I haven't seen anything else regarding this in Facebook documentation or from other stackoverflow questions. I feel like it must be doable since other Facebook programs have photo manipulation like this. Does anyone know? Thanks.</p>
  
  <p>Error: "Konva warning: Unable to get data URL. Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported."</p>