class FieldConfigAccessControlHandler

class FieldConfigAccessControlHandler extends EntityAccessControlHandler {
    
    /**
     * {@inheritdoc}
     */
    protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
        // Delegate access control to the underlying field storage config entity:
        // the field config entity merely handles configuration for a particular
        // bundle of an entity type, the bulk of the logic and configuration is with
        // the field storage config entity. Therefore, if an operation is allowed on
        // a certain field storage config entity, it should also be allowed for all
        // associated field config entities.
        // @see \Drupal\Core\Field\FieldDefinitionInterface
        
        /** \Drupal\field\FieldConfigInterface $entity */
        $field_storage_entity = $entity->getFieldStorageDefinition();
        return $field_storage_entity->access($operation, $account, TRUE);
    }

}