get a dataUrl for any img src on any domain.

getDataUrl.js

async function getDataUrl(src) {
  function run(resolve, reject) {
    const tmpImage = new Image();
    tmpImage.setAttribute('crossOrigin', 'Anonymous'); // NEEDED FOR CANVAS ANTI-TAINT
    tmpImage.src = src;
    tmpImage.onerror = reject; // no dataUrl
    tmpImage.onload = () => {
      const canvas = document.createElement('canvas');
      canvas.width = tmpImage.naturalWidth; // or .width;
      canvas.height = tmpImage.naturalHeight; // or .height;
      const context = canvas.getContext('2d');
      context.drawImage(tmpImage, 0, 0);
      const dataUrl = canvas.toDataURL();
      // console.log({dataUrl});
      resolve(dataUrl);
    };
  }
  return new Promise(run);
}