<!DOCTYPE html>
<html>
<body>
<svg width="200" height="200">
<filter id="feOffset" x="-40" y="-20"
width="100" height="200">
<feOffset in="SourceGraphic"
dx="60" dy="60" />
<feGaussianBlur stdDeviation="5"
result="blur2" />
<feMerge>
<feMergeNode in="BackgroundImage"
id="gfg" />
</feMerge>
</filter>
<rect x="40" y="40" width="100" height="100"
style="stroke: #000000; fill: red;
filter: url(#feOffset);" />
<rect x="40" y="40" width="100" height="100"
style="stroke: #000000; fill: red;" />
<script type="text/javascript">
let mergeNode = document.getElementById("gfg");
console.log(mergeNode.in1);
console.log("in1 value is : ",
mergeNode.in1.baseVal);
</script>
</svg>
</body>
</html>