odoo-saas-kubernetes/web_cohort/models/ir_action_act_window.py

# -*- coding: utf-8 -*-
from odoo import fields, models


class ActWindowView(models.Model):
    _inherit = 'ir.actions.act_window.view'

    view_mode = fields.Selection(selection_add=[
        ('cohort', 'Cohort')
    ], ondelete={'cohort': 'cascade'})