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 <svg width="100%" height="100%" preserveAspectRatio="none" 

      xmlns="http://www.w3.org/2000/svg"

      xmlns:xlink="http://www.w3.org/1999/xlink">

   <title>Testcase for scaled filter with non-integer x and y and objectBoundingBox</title> 

   <defs>

     <filter id="filter" filterUnits="objectBoundingBox" x="0.5" y="0.5" width="0.25" height="0.25">

       <feFlood flood-color="red" width="1" height="1" />

     </filter>

   </defs>

   <rect width="100%" height="100%" fill="lime"/>

   <g transform="scale(400)">

     <rect width="1" height="1" filter="url(#filter)" />

   </g>

   <rect x="200" y="200" width="100" height="100" fill="lime" />

 </svg>