<svg xmlns="http://www.w3.org/2000/svg" style="width: 100px; height: 100px;">

  <defs>
    <filter id="simpler">
      <feFlood flood-color="green"/>
    </filter>
  </defs>

  <rect style="fill: red" width="4167" height="100">
  </rect>

  <rect style="fill: #000099; filter:url(#simpler);" width="100" height="4167">
  </rect>

</svg>