Hi @idog
Thank you for contacting us. Nested tables aren’t officially support by Handsontable, and even as it is possible to display nested table with a custom renderer it’s still rather a workaround which has it’s flows, mainly not being able to edit the data inside the nested table.
I explained this in more details in this thread: Outermost table retains focus
As for now we don’t have this feature planned on our roadmap, but if that changes I will update you.