diff --git a/src/TocBuilder.php b/src/TocBuilder.php
index 19a6509eee..35342e1033 100644
--- a/src/TocBuilder.php
+++ b/src/TocBuilder.php
@@ -86,7 +86,7 @@ public function renderContent(TocInterface $toc) {
       ];

       $fragment_node = $dom->createDocumentFragment();
-      $html = Html::normalize($this->renderer->render($build));
+      $html = Html::normalize($this->renderer->renderPlain($build));
       $fragment_node->appendXML($html);

       // Replace the header node.
@@ -113,7 +113,7 @@ public function renderContent(TocInterface $toc) {
         '#item' => NULL,
       ];
       $fragment_node = $dom->createDocumentFragment();
-      $html = Html::normalize($this->renderer->render($build));
+      $html = Html::normalize($this->renderer->renderPlain($build));
       $fragment_node->appendXML($html);
       if (!empty($fragment_node->textContent)) {
         $dom->getElementsByTagName('body')->item(0)->appendChild($fragment_node);