chromium/third_party/blink/web_tests/external/wpt/css/css-masking/mask-image/support/image-with-ref.svg

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 200 200">
  <style>
    g { display: none; }
    g:target { display: inline; }
  </style>
  <g id="ref">
    <rect x="50" y="50" width="100" height="100" fill="black"/>
  </g>
</svg>