code: public function run(): void
      {
          $this->connection->query("
              ALTER TABLE
                  tl_layout
              ADD
                  minifyMarkup char(1) NOT NULL default ''
          ");
  
          // Enable the "minifyMarkup" option if it was enabled before
          if (isset($GLOBALS['TL_CONFIG']['minifyMarkup']) && $GLOBALS['TL_CONFIG']['minifyMarkup']) {
              $this->connection->query("
                  UPDATE
                      tl_layout
                  SET
                      minifyMarkup = '1'
              ");
          }
  
          // Add a .nosync file in every excluded folder
          if (!empty($GLOBALS['TL_CONFIG']['fileSyncExclude'])) {
              $fs = $this->container->get('filesystem');
              $uploadPath = $this->container->getParameter('contao.upload_path');
              $rootDir = $this->container->getParameter('kernel.project_dir');
              $folders = array_map('trim', explode(',', $GLOBALS['TL_CONFIG']['fileSyncExclude']));
  
              foreach ($folders as $folder) {
                  if (is_dir($rootDir.'/'.$uploadPath.'/'.$folder)) {
                      $fs->touch($rootDir.'/'.$uploadPath.'/'.$folder.'/.nosync');
                  }
              }
          }
  
          $schemaManager = $this->connection->getSchemaManager();
  
          if ($schemaManager->tablesExist(['tl_comments_notify'])) {
              $this->connection->query("
                  ALTER TABLE
                      tl_comments_notify
                  ADD
                      active CHAR(1) DEFAULT '' NOT NULL
              ");
  
              $this->connection->query("
                  UPDATE
                      tl_comments_notify
                  SET
                      active = '1'
                  WHERE
                      tokenConfirm = ''
              ");
          }
      }
docs: {@inheritdoc}