code: protected function addParentCondition()
      {
          if ($this->inputScreen['meta']['rendertype'] === 'standalone') {
              return;
          }
  
          $setter  = [['to_field' => 'pid', 'from_field' => 'id']];
          $inverse = [];
  
          /** @var ParentChildConditionInterface $relationship */
          $relationship = $this->definition->getChildCondition(
              $this->inputScreen['meta']['ptable'],
              $this->container->getName()
          );
          if (!$relationship instanceof ParentChildConditionInterface) {
              $relationship = new ParentChildCondition();
              $relationship
                  ->setSourceName($this->inputScreen['meta']['ptable'])
                  ->setDestinationName($this->container->getName());
              $this->definition->addChildCondition($relationship);
          } else {
              $setter  = array_merge_recursive($setter, $relationship->getSetters());
              $inverse = array_merge_recursive($inverse, $relationship->getInverseFilterArray());
          }
  
          // For tl_ prefix, the only unique target can be the id?
          // maybe load parent dc and scan for unique in config then.
          $relationship
              ->setFilterArray(
                  FilterBuilder::fromArray($relationship->getFilterArray())
                      ->getFilter()
                      ->andRemotePropertyEquals('pid', 'id')
                      ->getAllAsArray()
              )
              ->setSetters($setter)
              ->setInverseFilterArray($inverse);
      }
docs: Parse the correct conditions for a MetaModel with variant support.
  
  @return void