'When changing the object_create type configuration:
- `new` and `copy_current`: crud_model_id is the same as base model
- `new_other`: user choose crud_model_id
- `copy_other`: disassemble the reference object to have its model
- if the target model has changed, then reset the link field that is
probably not correct anymore'

def _onchange_create_config(self):

    crud_model_id = self.crud_model_id
    if (self.use_create == 'new'):
        self.crud_model_id = self.model_id
    elif (self.use_create == 'new_other'):
        pass
    elif (self.use_create == 'copy_current'):
        self.crud_model_id = self.model_id
    elif ((self.use_create == 'copy_other') and self.ref_object):
        ref_model = self.ref_object._name
        self.crud_model_id = self.env['ir.model'].search([('model', '=', ref_model)])
    if (self.crud_model_id != crud_model_id):
        self.link_field_id = False
