_civicrm_group_roles_validate_groups(): Argument #1 ($group_ids) must be of type array, null given
From https://forum.backdropcms.org/forum/create-user-civicrm-installed
_civicrm_group_roles_validate_groups(): Argument #1 (closed) ($group_ids) must be of type array, null given, called in /var/www/backdrop/modules/civicrm/backdrop/modules/civicrm_group_roles/civicrm_group_roles.module on line 108