Фильтр feBlend не работает

<svg viewBox="0 0 520 520" width="500" style='border: 1px solid black'>
<rect x ="5" y="5" width="190" height="490"
stroke="blue" stroke-width="2" fill="none" ></rect>

<defs>
<linearGradient id="MyGradient" >
<stop offset="0" stop-color="#000000" />
<stop offset=".33" stop-color="#ffffff" />
<stop offset=".67" stop-color="#ff0000" />
<stop offset="1" stop-color="#808080" />
</linearGradient>
<filter id="Normal">
<feBlend mode="normal" in2="BackgroundImage" in="SourceGraphic"/>
</filter>
<filter id="Multiply">
<feBlend mode="multiply" in2="BackgroundImage" in="SourceGraphic"/>
</filter>
<filter id="Screen">
<feBlend mode="screen" in2="BackgroundImage" in="SourceGraphic"/>
</filter>
<filter id="Darken">
<feBlend mode="darken" in2="BackgroundImage" in="SourceGraphic"/>
</filter>
<filter id="Lighten">
<feBlend mode="lighten" in2="BackgroundImage" in="SourceGraphic"/>
</filter>
</defs>

<g enable-background="new" >
<rect x="100" y="10" width="90" height="480"
fill="url(#MyGradient)"/>
<rect x="20" y="20" width="160" height="50"
fill="blue" filter="url(#Normal)" ></rect>
<rect x="20" y="120" width="160" height="50"
fill="blue" filter="url(#Multiply)" ></rect>
<rect x="20" y="220" width="160" height="50"
fill="blue" filter="url(#Screen)" ></rect>
<rect x="20" y="320" width="160" height="50"
fill="blue" filter="url(#Darken)" ></rect>
<rect x="20" y="420" width="160" height="50"
fill="blue" filter="url(#Lighten)" ></rect>
</g>
</rect>

</svg>