public static function supports_svg() {
        // IE 5 - 8 don't support SVG at all.
        $instance = self::instance();
        if ($instance->supportssvg === null) {
            if ($instance->useragent === false) {
                // Can't be sure, just say no.
                $instance->supportssvg = false;
            } else if (self::check_ie_version('0') and !self::check_ie_version('9')) {
                // IE < 9 doesn't support SVG. Say no.
                $instance->supportssvg = false;
            } else if (self::is_ie() and !self::check_ie_version('10') and self::check_ie_compatibility_view()) {
                // IE 9 Compatibility View doesn't support SVG. Say no.
                $instance->supportssvg = false;
            } else if (preg_match('#Android +[0-2]\.#', $instance->useragent)) {
                // Android < 3 doesn't support SVG. Say no.
                $instance->supportssvg = false;
            } else if (self::is_opera()) {
                // Opera 12 still does not support SVG well enough. Say no.
                $instance->supportssvg = false;
            } else {
                // Presumed fine.
                $instance->supportssvg = true;
            }
        }
        return $instance->supportssvg;
    }