Svg
Compare your SVG output to any of the images here:
You are missing ids in your SVG output like id="background", id="icon", etc.
Here is the raw output of car.svg:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<svg
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:cc="http://creativecommons.org/ns#"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:svg="http://www.w3.org/2000/svg"
xmlns="http://www.w3.org/2000/svg"
xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
width="40"
height="40"
viewBox="0 0 40 40"
id="svg4145"
version="1.1"
sodipodi:docname="car.svg">
<defs
id="defs4147" />
<sodipodi:namedview
id="base"
pagecolor="#ffffff"
bordercolor="#666666"
borderopacity="1.0"
showgrid="false"
units="px" />
<metadata
id="metadata4150">
<rdf:RDF>
<cc:Work
rdf:about="">
<dc:format>image/svg+xml</dc:format>
<dc:type
rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
<dc:title></dc:title>
</cc:Work>
</rdf:RDF>
</metadata>
<g
id="layer1">
<path
style="fill:#008000;fill-opacity:1;stroke:#333333;stroke-width:1.89999998;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1"
d="M 20.001953 3.6816406 L 18.871094 7.0722656 A 12.37437 12.37437 0 0 1 20.001953 7.0097656 A 12.37437 12.37437 0 0 1 21.130859 7.0664062 L 20.001953 3.6816406 z M 20 7.625 A 12.37437 12.37437 0 0 0 7.625 20 A 12.37437 12.37437 0 0 0 20 32.375 A 12.37437 12.37437 0 0 0 32.375 20 A 12.37437 12.37437 0 0 0 20 7.625 z "
id="background" />
<path
id="icon"
style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:medium;line-height:125%;font-family:FontAwesome;-inkscape-font-specification:'FontAwesome, Normal';text-align:start;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:#333333;stroke-width:0.1;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;stroke-miterlimit:4;stroke-dasharray:none"
d="m 15.028653,22.29641 q 0.395353,-0.395353 0.395353,-0.950528 0,-0.555177 -0.395353,-0.95053 Q 14.633301,20 14.078125,20 q -0.555176,0 -0.950528,0.395352 -0.395353,0.395353 -0.395353,0.95053 0,0.555175 0.395353,0.950528 0.395352,0.395352 0.950528,0.395352 0.555176,0 0.950528,-0.395352 z m 0.698176,-3.642291 8.546345,0 -0.748646,-3.002997 q -0.01682,-0.06729 -0.117769,-0.143 -0.100935,-0.08412 -0.176646,-0.08412 l -6.46023,0 q -0.07572,0 -0.176647,0.08412 -0.100946,0.07571 -0.117767,0.143 l -0.748648,3.002997 z m 11.145578,3.642291 q 0.395352,-0.395353 0.395352,-0.950528 0,-0.555177 -0.395352,-0.95053 Q 26.477054,20 25.921879,20 q -0.555177,0 -0.95053,0.395352 -0.395352,0.395353 -0.395352,0.95053 0,0.555175 0.395352,0.950528 0.395353,0.395352 0.95053,0.395352 0.555175,0 0.950528,-0.395352 z m 1.741234,-1.758057 0,3.230113 q 0,0.11777 -0.07571,0.193472 -0.07572,0.07571 -0.193472,0.07571 l -0.807528,0 0,1.076704 q 0,0.67294 -0.471058,1.143998 -0.471059,0.471059 -1.144,0.471059 -0.672941,0 -1.143999,-0.471059 -0.471058,-0.471058 -0.471058,-1.143998 l 0,-1.076704 -8.613639,0 0,1.076704 q 0,0.67294 -0.471058,1.143998 -0.471059,0.471059 -1.144,0.471059 -0.672939,0 -1.143998,-0.471059 -0.471057,-0.47106 -0.471057,-1.143999 l 0,-1.076705 -0.807529,0 q -0.117769,0 -0.193472,-0.07571 -0.07571,-0.07572 -0.07571,-0.193472 l 0,-3.230114 q 0,-0.782294 0.546764,-1.329058 0.555177,-0.555176 1.337469,-0.555176 l 0.23553,0 0.883235,-3.524525 q 0.19347,-0.790705 0.874822,-1.320646 0.681352,-0.538353 1.505705,-0.538353 l 6.460229,0 q 0.824353,0 1.505705,0.538353 0.681352,0.529941 0.874822,1.320646 l 0.883234,3.524525 0.23553,0 q 0.782293,0 1.329058,0.555176 0.555176,0.546764 0.555176,1.329058 z" />
</g>
</svg>
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