Show many-to-many values in grid


at the moment I have two tables customer and category and an extra table with a many-to-many relation
The entry form works fine and now I would like to show all categories per customer in a customer grid. But i have idea how can i realize it.

I hope someone has a good idea.

Kind regards

I would create a view on the join table to the Categories table and use it as the detail on a master-detail display