bizcharts tooltip颜色显示问题

Question

给柱状图设置了渐变背景色后，tooltip的小圆点(marker)的颜色都变成了黑色的，它应该识别不了`
l (90) 0:#FF9E4C 1:#FB6051这种写法

<div className={barClassName} ref={this.handleRoot}>

        <div className={styles.chart} ref={this.handleRef}>
            { title && (<h4 className={styles.title}>{title}</h4>) }
            <Chart 
                height={title ? height - 31 : height}
                data={dv} 
                forceFit={forceFit}
                onGetG2Instance={this.getG2Instance}
            >
                <Coord scale={scale} />
                <Axis name="x" />
                <Axis name="y" 
                    label={autoHideXLabels ? undefined : {}}
                    tickLine={autoHideXLabels ? undefined : {}}
                />
                <Tooltip
                    crosshairs={{
                        type: "y"
                    }}
                />
                <Geom
                    type="interval"
                    position="x*y"
                    active={true}
                    color={['name', [
                        'l (90) 0:#FF9E4C 1:#FB6051',
                        'l (90) 0:#FF69A6 1:#FF3636',
                        'l (90) 0:#4BFCFA 1:#199EFF',
                        'l (90) 0:#D6F417 1:#46BD16',
                        'l (90) 0:#B8DEFF 1:#5D80A4',
                    ]]}
                    adjust={[
                    {
                        type: "dodge",
                        marginRatio: 1 / 32
                    }
                    ]}
                />
            </Chart>
            {hasLegend && (
                <ul className={styles.legend}>
                    {legendData.map((item, i) => (
                        <li key={i}>
                        <span
                            className={styles.dot}
                            style={{
                                background: !item.checked ? '#aaa' : `linear-gradient(to bottom, ${item.colors.topColor}, ${item.colors.bottomColor})`
                            }}
                        />
                        <span 
                            className={styles.legendTitle} 
                            style={{color: item.colors.bottomColor}}
                        >
                            {item.name}
                        </span>
                        </li>
                    ))}
                </ul>
            )}
        </div>
    </div>