How to add a datasheet-style (grid) form/field in LibreOffice Base design view?

Question

When creating a LibreOffice Base form via the Wizard, it is possible to choose a 'datasheet' style for the selected fields. The fields become part of a Mainform_Grid and/or Subform_Grid item if you look at the form in Form Navigator in Design View.

How can I add a new subform with datasheet (grid) style to an existing form while in Design View? After adding the Subform/Table, I only see the 'Add Field' option which creates a label+field combo. (The reason for wanting to do this in Design View is that it's a subform which depends on another subform, so I cannot add it via the Wizard. Another motivation might be when you want to add a field to an existing grid-style form, and not wanting to re-do the existing layout and styling.).

Answer 1

Mainform_Grid is a Table Control. To add another Table Control, use the Form Controls toolbar. There is an icon called More Controls, which brings up an option to add a Table Control.

Now it looks like this in Form Navigator:

Documentation: https://help.libreoffice.org/Common/More_Controls#Table_Control