chromium/third_party/blink/web_tests/svg/custom/external-paintserver-reference.svg

<?xml version="1.0" standalone="no"?>
<html xmlns="http://www.w3.org/1999/xhtml" style="height:100%">
  <!-- There should be no red on the page -->
  <svg width="100%" height="100%" version="1.1" style="display: block"
       xmlns="http://www.w3.org/2000/svg">

    <defs>
      <linearGradient id="orange_red" x1="0%" y1="0%" x2="100%" y2="0%">
        <stop offset="0%" style="stop-color:red;"/>
        <stop offset="100%" style="stop-color:red;"/>
      </linearGradient>
    </defs>

    <rect x="0" y="0" width="100" height="100" style="fill: url(http://www.example.com/something#orange_red)"/>
  </svg>
</html>