function getImageElementsWithSrcUrl(srcUrl) {
  const imgElArr = Array.from(document.getElementsByTagName('img'));
  const filtImgElArr = imgElArr.filter(x => x.src === srcUrl);
  return filtImgElArr;
}
Returns a list of all DOM image elements pointing to the provided srcUrl.
@param {string} srcUrl which url to search for, including 'http(s)://'
    prefix.
@returns {HTMLElement[]} all img elements pointing to the provided srcUrl