Horizontal and vertical grid lines can be shown across a diagram's rows.
Grid line options
Menu: Diagram | Grid
The color and line style are configurable.
At which unit vert. grid lines start, and how they are spaced, are both configurable.
Show or hide hor. grid lines with
Menu: View | Show hor. grid
Show or hide vert. grid lines with
Menu: View | Show vert. grid
Grid line Features
Vertical Grid line Styles
Horizontal Grid line Styles