In a combination chart when multiple scale option is chosen then we would have two value axis (left y-axis and right y-axis). When a target reference line is added through the option lines and curves, two lines appears for two different scales. we can mitigate the problem when both the scales on value axis are same, but problem arises when scales are of different range. Also changing the color of the line option is disabled. It would be good to enable the option for changing the line color and an option to show/hide the target reference lines individual for each value axis.