old_contents: # Copyright (C) 2020 Open Source Integrators
  # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
  from odoo import fields, models
  
  
  class Animal(models.Model):
      _inherit = "animal"
  
      partner_id = fields.Many2one(
          "res.partner", string="Owner", index=True, track_visibility="onchange"
      )
  
new_contents: # Copyright (C) 2020 Open Source Integrators
  # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
  from odoo import fields, models
  
  
  class Animal(models.Model):
      _inherit = "animal"
  
      partner_id = fields.Many2one(
          "res.partner", string="Owner", index=True, tracking=True
      )
  
subject: Fix tracking parameter