public function indexAction(NodeInterface $node = null)
    {
        $this->session->start();
        $this->session->putData('__neosLegacyUiEnabled__', false);
        $user = $this->userService->getBackendUser();

        if ($user === null) {
            $this->redirectToUri($this->uriBuilder->uriFor('index', [], 'Login', 'Neos.Neos'));
        }

        if ($node === null) {
            $node = $this->findNodeToEdit();
        }

        $siteNode = $node->getContext()->getCurrentSiteNode();

        $this->view->assign('user', $user);
        $this->view->assign('documentNode', $node);
        $this->view->assign('site', $siteNode);
        $this->view->assign('clipboardNode', $this->clipboard->getNodeContextPath());
        $this->view->assign('clipboardMode', $this->clipboard->getMode());
        $this->view->assign('headScripts', $this->styleAndJavascriptInclusionService->getHeadScripts());
        $this->view->assign('headStylesheets', $this->styleAndJavascriptInclusionService->getHeadStylesheets());
        $this->view->assign('splashScreenPartial', $this->settings['splashScreen']['partial']);
        $this->view->assign('sitesForMenu', $this->menuHelper->buildSiteList($this->getControllerContext()));

        $this->view->assign('interfaceLanguage', $this->userService->getInterfaceLanguage());
    }