Row groups are used in a form, and more specifically only in static grids, to create a sectional separation between rows in a grid.
In order to create a functional row group, you must merge all the cells of the same row, for the number of columns you have.
In the example below, since the grid has 5 columns, the 5 cells of the same row have been merged.
By programming your grid like this, the form in Paperless Forms will show sections that will be visible as long as you are inside it.
Important points
This feature is only available in static grids and will not work in a dynamic grid.
If you want to use sections (or "row groups") in your grids, you must absolutely start your grid with a section.
It is not possible to put several sections on top of each other.
There is no limit to the number of sections (or "row groups") you can create in a grid.