Odoo-18.0-20251222/web_ir_actions_act_multi/readme/USAGE.md

To use this functionality you need to return following action with list of actions to execute:

def foo(self):
   self.ensure_one()
   return {
      'type': 'ir.actions.act_multi',
      'actions': [
          {'type': 'ir.actions.act_window_close'},
          {'type': 'ir.actions.client', 'tag': 'reload'},
      ]
   }