I have a 1095 bytes svg file that works in chrome, but Firefox and Internet Explorer somehow remove one of the components, can you fix this?

Question

The bottom rectangle is missing, if I change the top of that invisible rectangle 1 pixel up or down it becomes a 1 pixel line, very strange.
<pre><nowiki><?xml version="1.0" standalone="no"?>
<svg width="3cm" height="3cm" viewBox="0 0 1000 1000"
xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny">
<title>Genetics Logo</title>
<desc>Genetics Logo</desc>
<mask id="circles">
<rect fill="white" width="100%" height="100%"/>
<circle fill="black" cx="846" cy="800" r="170"/>
<circle fill="black" cx="500" cy="200" r="170"/>
<circle fill="black" cx="500" cy="600" r="190"/>
<circle fill="black" cx="154" cy="800" r="170"/>
</mask>
<polyline stroke="black" stroke-width="140" points="154,800 500,200" mask="url(#circles)"/>
<polyline stroke="black" stroke-width="140" points="846,800 500,200" mask="url(#circles)"/>
<polyline stroke="black" stroke-width="140" points="154,800 846,800" mask="url(#circles)"/>
<circle class="CtlPoint" cx="154" cy="800" r="130"/>
<circle class="CtlPoint" cx="846" cy="800" r="130" />
<circle class="CtlPoint" cx="500" cy="200" r="130" />
<circle class="CtlPoint" cx="500" cy="600" r="150" fill="#C00"/>
</svg></nowiki></pre>

Answer 1

Added 2 images to show the difference:
* Chrome renders the svg correctly with the bottom bar
* Firefox leaves out the bottom bar