code: public function postDispatch()
      {
          if ($this->view instanceof Zend_View_Interface) {
              // Common variables used in all views.
              $this->view->assign([
                  'errors'    => $this->_errors,
                  'messages'  => $this->_messages,
                  'title'     => $this->_title,
              ]);
  
              // XMLHttpRequest requests should not render the entire layout,
              // only the correct templates related to the action.
              if ($this->getRequest()->isXmlHttpRequest()) {
                  $this->getHelper('layout')->disableLayout();
              }
  
              $this->getResponse()->setHeader('Content-Type', 'text/html; charset=utf-8', true);
          }
      }
docs: Post-dispatch routines.
  
  Common usages for `postDispatch()` include rendering content in a
  sitewide template, link url correction, setting headers, etc.