Overrides BlockPluginTrait::blockSubmit
public function blockSubmit($form, FormStateInterface $form_state) { // Handle the #empty_value: using the default requires specifying `null` in // the config. // @see search.schema.yml // @see \Drupal\search\Form\SearchBlockForm::buildForm() $this->configuration['page_id'] = $form_state->getValue('page_id') ?: NULL; }