With https://github.com/odoo/odoo/commit/ac8b0fcfc5299b5ea62543b8382cb419fed4868e, the 'country_events' class was renamed to 'oe_country_events'. This was done correctly for JS animations and snippets but not for the 'Country Events' option in the customize menu. This made the option useless. This commit solves the problem by supporting the two classes (as it is a stable fix). closes odoo/odoo#30662