Google Maps - SVG marker cut off

Why my svg icons for google.maps.Marker are cut off? I tried many of combinations with size and scaledSize...

var marker = new google.maps.Marker({
            position: new google.maps.LatLng({lat: el.lat, lng: el.lon}),
            icon: {
                url: "/images/icons/observation_" + el.rate + ".svg",
                size: new google.maps.Size(20, 20),
                origin: new google.maps.Point(0, 0),
                anchor: new google.maps.Point(10, 10),
                scaledSize: new google.maps.Size(20, 20)
            },
            zIndex: 6,
            map: map.map
        });

Svg icons should by 20x20 px.

https://jsfiddle.net/d3v5huzr/

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