Revision control
++ <?xml version="1.0" encoding="UTF-8"?>
++ <!-- Test that <use> works correctly inside <symbol>, <marker>, and <pattern> -->
++ <svg width="300" height="100" viewBox="0 0 300 100" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
++ <defs>
++ <!-- use inside symbol -->
++ <circle id="dot" cx="50" cy="50" r="40" fill="red"/>
++ <symbol id="dotSymbol" overflow="visible">
++ <use xlink:href="#dot"/>
++ </symbol>
++
++ <!-- use inside marker -->
++ <rect id="markerBox" x="0" y="0" width="10" height="10" fill="green"/>
++ <marker id="m" viewBox="0 0 10 10" markerWidth="10" markerHeight="10" refX="5" refY="5">
++ <use xlink:href="#markerBox"/>
++ </marker>
++
++ <!-- use inside pattern -->
++ <rect id="tile" width="20" height="20" fill="blue"/>
++ <pattern id="p" patternUnits="userSpaceOnUse" width="20" height="20">
++ <use xlink:href="#tile"/>
++ </pattern>
++ </defs>
++
++ <!-- symbol: red circle -->
++ <use xlink:href="#dotSymbol" x="0" y="0"/>
++
++ <!-- marker: green squares on line endpoints -->
++ <line x1="150" y1="50" x2="150" y2="50" stroke="black" stroke-width="1" marker-start="url(#m)"/>
++
++ <!-- pattern: blue tiled rectangle -->
++ <rect x="200" y="0" width="100" height="100" fill="url(#p)"/>
++ </svg>