filterEmbeddedResponse example

'scripts_bottom' => $js_bottom_placeholder,
          ],
        ],
      ]);
      $html_response->getCacheableMetadata()->setCacheMaxAge(0);

      // Push a fake request with the asset libraries loaded so far and dispatch       // KernelEvents::RESPONSE event. This results in the attachments for the       // HTML response being processed by HtmlResponseAttachmentsProcessor and       // hence the HTML to load the bottom JavaScript can be rendered.       $fake_request = $this->requestStack->getMainRequest()->duplicate();
      $html_response = $this->filterEmbeddedResponse($fake_request, $html_response);
      $scripts_bottom = $html_response->getContent();
    }

    $this->sendChunk($scripts_bottom);
  }

  /** * Sends no-JS BigPipe placeholders' replacements as embedded HTML responses. * * @param string $html * HTML markup. * @param array $no_js_placeholders * Associative array; the no-JS BigPipe placeholders. Keys are the BigPipe * selectors. * @param \Drupal\Core\Asset\AttachedAssetsInterface $cumulative_assets * The cumulative assets sent so far; to be updated while rendering no-JS * BigPipe placeholders. * * @throws \Exception * If an exception is thrown during the rendering of a placeholder, it is * caught to allow the other placeholders to still be replaced. But when * error logging is configured to be verbose, the exception is rethrown to * simplify debugging. */