These were in SVG 1.1 put have been removed: http://www.w3.org/TR/SVG11/struct.html#InterfaceSVGSVGElement http://www.w3.org/TR/SVG2/struct.html#InterfaceSVGSVGElement These properties all return the constant 0.2645833194255829 on all platforms, so they don't do what their names suggest.
Docs: https://developer.mozilla.org/en-US/docs/Web/API/SVGSVGElement#Browser_compatibility