Hi Ray,

many thanks for your reply! For the list view it is working now. This is perfect and helps a lot. In the form view it is not working. I tried to find examples within the odoo models (e.g. res.user that you've mentioned). Unfortunately none of them seems to use the list.many2one widget for many2many fields.

Any further advice will be greatly appreciated.

Many thanks and best wishes

Carl

This widget is not in v14 and was removed some time ago.

For a Form View, use:

 widget="list.many2one"

To get:

For a List View, the default display of a one2many and many2many field in a list already shows the number of records:

From sale.order, and from res_partner: