The widget many2onebutton doesn't exist anymore. As the web client fallbacked on the default many2one widget. The behavior was the intended one but with a warning in the logs. This commit uses the proper widget to avoid the unintentional warning closes odoo/odoo#76882 X-original-commit: 4547cbff9f2850fcfcd536a574fd5c29c44ecdb5 Signed-off-by: William Henrotin <Whenrow@users.noreply.github.com>