Hi there, I am working on a custom module that inherits "res.partner" from "purchase" module.

When the customer requested the mail thread and mail activity functionality, I inherited them as well such as that:

_inherit = ["res.partner", "mail.thread", "mail.activity.mixin"]

It failed to read from the database, so I simplified this to be:

_inherit = ["res.partner", "mail.thread",]

, and I found this duplication error:

TypeError: Many2many fields res_partner.category_id and res.partner.category_id use the same table and columns

So, are there any suggestions to inherit safely from multiple modules?

By the way I know about delegation, and I can combine it with classical inheritance. Do I need to solve it without delegation if possible?

* Maybe this means that MailThread is already previously imported.