Can't add items to Many2many in Odoo 12 EE
I defined a `Many2many` field for `ir.attachemnt`. The problem is i can' see the `Add an item` link to add the records.
attachment_ids = fields.Many2many('ir.attachment', string='Attachments')
I also tried this:
<field name="attachment_ids" widget="many2many" />
Is it bug or did i miss anything? Any idea?