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                <p>The red circle is revealed by a mask, green by a clip-path and blue is just a square showing what the mask and clip-path are doing. The mask scale will work in Chrome, but not FF, IE and Edge. Clip-path scale will work in Chrome, IE and Edge, but not FF.<p>
<svg id="demo" xmlns="" width="400" height="400" viewBox="0 0 200 200">
<mask id="theMask">
<rect class="theSquare" x="0" y="0" width="100" height="100" fill="#fff" />
<clipPath id="theClip">
<rect class="theSquare" x="100" y="0" width="100" height="100" fill="#fff" />

<g id="clipReveal" clip-path="url(#theClip)">
	<circle r="50" fill="green" cx="150" cy="50" />

<g id="maskReveal" mask="url(#theMask)"> 
	<circle r="50" fill="red" cx="50" cy="50" />
<rect class="theSquare" x="0" y="100" width="100" height="100" fill="navy" />



                p {
  font-size: 1.25em;


                var tl = new TimelineMax(),
    element = $(".theSquare"), 1, {attr:{width:50}});, 1, {attr:{height:50}});, 1, {attr:{x:"+=50"}, yoyo:true, repeat:1});, 1, {attr:{width:100,height:100}});, 1, {transformOrigin:"center", scale:.5, repeat:1, yoyo:true, repeatDelay:0.5});