Since [1], the way the message unread counter is computed has changed. The patch of the `im_livechat` module is not adapted properly. This commit fixes this issue. [1]: 6ebe033b00774ed8824d05f0adf9dae5f3654261 closes odoo/odoo#118581 Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>