diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index f2bce97ff3368c9640e1914a3d9f1df64b0daed3..7ece51e4bf5aa0c9312f7acbc23ff1d81f5be106 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -1375,7 +1375,7 @@ function template_preprocess_page(&$variables) {
     $variables['db_is_active'] = FALSE;
   }
 
-  if ($node = \Drupal::routeMatch()->getParameter('node')) {
+  if (($node = \Drupal::routeMatch()->getParameter('node')) || ($node = \Drupal::routeMatch()->getParameter('node_preview'))) {
     $variables['node'] = $node;
   }
 }
diff --git a/core/profiles/demo_umami/tests/src/Functional/DemoUmamiProfileTest.php b/core/profiles/demo_umami/tests/src/Functional/DemoUmamiProfileTest.php
index 89f6a6a20ead70fdf1adc485cde4935a625205e4..39b9b2bddf7daa0356e3b055d8f18c76a47022a0 100644
--- a/core/profiles/demo_umami/tests/src/Functional/DemoUmamiProfileTest.php
+++ b/core/profiles/demo_umami/tests/src/Functional/DemoUmamiProfileTest.php
@@ -128,6 +128,12 @@ public function testEditNodesByAdmin() {
     $node = reset($nodes);
     $this->drupalGet($node->toUrl('edit-form'));
     $webassert->statusCodeEquals('200');
+
+    $this->submitForm([], 'Preview');
+    $webassert->statusCodeEquals('200');
+    $this->assertSession()->elementsCount('css', 'h1', 1);
+    $this->clickLink('Back to content editing');
+
     $this->submitForm([], "Save");
     $webassert->pageTextContains('Recipe Deep mediterranean quiche has been updated.');
   }