diff -u b/core/tests/Drupal/FunctionalJavascriptTests/Core/Render/Element/VerticalTabsTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Core/Render/Element/VerticalTabsTest.php
--- b/core/tests/Drupal/FunctionalJavascriptTests/Core/Render/Element/VerticalTabsTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Core/Render/Element/VerticalTabsTest.php
@@ -5,7 +5,7 @@
 use Drupal\FunctionalJavascriptTests\JavascriptTestBase;
 
 /**
- * Tests that sessions don't expire.
+ * Tests that child errors are displayed on vertical tabs.
  *
  * @group Render
  */