y above exists in the "list of
  // available images". As per the spec's #updating-the-image-data algorithm [1]
  // step 6, the "list of avalable images" is consulted before we take any
  // lazyload-specific action. This means that lazyload images can load eagerly
  // if they target a resource in the list of available images, which the image
  // below is doing.
  //
  // Note that if https://github.com/whatwg/html/issues/7005 resolves in favor
  // of allowing in-flight image requests to be placed in th