Mask setting information which separates data row under the mouse.
The default value of visible property has been reset as false. In other words, in order to display mask, visible should be specified as true. And, since it is drawn over the existing data cells, translucent background style must be specified. The default value is "#20aaaaaa".
It is used as DisplayOptions.rowHoverMask property.
grid.displayOptions().setRowHoverMask({
visible: true,
styles: {
background: "#20ff0000"
}
};