Problem ------- Since https://github.com/odoo/odoo/commit/d3b18979bfb5496fa4370fdf03a806c469127730, when a visitor register for an event, the fields in the POST are checked against a list of allowed fields. The list is hardcoded inside the method _process_attendees_form. Solution -------- Move this list in a specific method that can be easily overidden by another module closes odoo/odoo#67080 X-original-commit: ebadf16c7c38ca52ec4c5ce871c2584aaa98b91d Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com> Signed-off-by: Thibault Francois <tfr-odoo@users.noreply.github.com>