code: public function getDerivativeDefinitions($base_plugin_definition) {
      if ($this->moduleHandler->moduleExists('content_lock') && $this->routeProvider->getRoutesByNames(['view.locked_content.page_1'])) {
        $this->derivatives["thunder_article.content_lock"] = [
          'route_name' => "view.locked_content.page_1",
          'title' => $this->t('Locked content'),
          'parent_id' => "system.admin_content",
          'weight' => 2,
        ] + $base_plugin_definition;
      }
  
      if ($this->moduleHandler->moduleExists('scheduler') && $this->routeProvider->getRoutesByNames(['view.scheduler_scheduled_content.overview'])) {
        // See thunder_article_menu_local_tasks_alter() for how this is displayed
        // or not depending on configuration.
        $this->derivatives["thunder_article.scheduler"] = [
          'route_name' => "view.scheduler_scheduled_content.overview",
          'title' => $this->t('Scheduled content'),
          'parent_id' => "system.admin_content",
          'weight' => 3,
          'cache_tags' => $this->configFactory->get('thunder_article.settings')->getCacheTags(),
        ] + $base_plugin_definition;
      }
  
      if ($this->moduleHandler->moduleExists('access_unpublished') && $this->routeProvider->getRoutesByNames(['access_unpublished.access_token.list'])) {
        $this->derivatives["thunder_article.access_unpublished"] = [
          'route_name' => "access_unpublished.access_token.list",
          'title' => $this->t('Unpublished access'),
          'parent_id' => "system.admin_content",
          'weight' => 4,
        ] + $base_plugin_definition;
      }
  
      return $this->derivatives;
    }
docs: {@inheritdoc}