code: private function buildBackendMenuSection($groupName, Request $request)
      {
          $strRefererId = $request->attributes->get('_contao_referer_id');
  
          $label = $this->translator->trans('MOD.' . $groupName, [], 'contao_modules');
  
          if (\is_array($label)) {
              $label = $label[0];
          }
  
          return [
              'class'   => ' node-expanded',
              'title'   => StringUtil::specialchars($this->translator->trans('MSC.collapseNode', [], 'contao_modules')),
              'label'   => $label,
              'href'    => $this->urlGenerator->generate(
                  'contao_backend',
                  ['do' => $request->get('do'), 'mtg' => $groupName, 'ref' => $strRefererId]
              ),
              'ajaxUrl' => $this->urlGenerator->generate('contao_backend'),
              // backwards compatibility with e.g. EasyThemes
              'icon'    => 'modPlus.gif',
              'modules'  => [],
          ];
      }
docs: Build a menu section.
  
  @param string  $groupName The group name.
  @param Request $request   The current request.
  
  @return array