I tried to use the following method to position CustomColorDialog relative to ColorPicker.

public static Point2D pointRelativeTo(Object parent, double width,
            double height, double screenX, double screenY, HPos hpos, VPos vpos)

I specify:

screenX = colorPicker.getX() + colorPicker.getWidth()
screenY = colorPicker.getY()
hpos = HPos.RIGHT
vpos = VPos.CENTER

When there is enough space to the left or to the right from the colorPicker, window is positioned correctly.
Otherwise, it is positioned to the leftmost screen position. This doesn't seem to be correct. According to my hpos variable, I want it to be positioned to the right.

So I didn't use this method in my fix to RT-27001