code: protected function removeEmptyDetailPages($jumpTos)
      {
          // Remove the detail pages.
          foreach ($jumpTos as $jumpTo) {
              // Get the page from the url.
              $event = new GetPageDetailsEvent($jumpTo['value']);
              $this->getEventDispatcher()->dispatch(ContaoEvents::CONTROLLER_GET_PAGE_DETAILS, $event);
  
              $pageDetails = $event->getPageDetails();
  
              // Check if we have a page If not go to the next one.
              if ($pageDetails === null) {
                  continue;
              }
  
              // Make a full url from it.
              $baseUrl = $this->getBaseUrl($pageDetails);
  
              if (($strKey = array_search($baseUrl->getUrl(), $this->foundPages)) !== false) {
                  unset($this->foundPages[$strKey]);
              }
  
              // Make a full url from it without the https.
              $baseUrl = $this->getBaseUrl($pageDetails, null, true);
  
              if (($strKey = array_search($baseUrl->getUrl(), $this->foundPages)) !== false) {
                  unset($this->foundPages[$strKey]);
              }
          }
      }
docs: Remove all empty detail pages.
  
  @param array $jumpTos A list with the jumpTo pages.
  
  @return void