diff --git a/core/tests/Drupal/Tests/Core/Render/RendererTest.php b/core/tests/Drupal/Tests/Core/Render/RendererTest.php
index 708a92d..c485876 100644
--- a/core/tests/Drupal/Tests/Core/Render/RendererTest.php
+++ b/core/tests/Drupal/Tests/Core/Render/RendererTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\Tests\Core\Render;
 
 use Drupal\Core\Cache\Cache;
-use Drupal\Core\Cache\CacheableDependencyInterface;
 use Drupal\Core\Render\Element;
 use Drupal\Core\Template\Attribute;
 
@@ -323,10 +322,7 @@ public function testRenderSorting() {
     // Confirm that the $elements array has '#sorted' set to TRUE.
     $this->assertTrue($elements['#sorted'], "'#sorted' => TRUE was added to the array");
 
-    // Pass $elements through \Drupal\Core\Render\Element::children() and
-    // ensure it remains sorted in the correct order.
-    // \Drupal::service('renderer')->render() will return an empty string if
-    // used on the same array in the same request.
+    // Pass $elements through \Drupal\Core\Render\Element::children().
     $children = Element::children($elements);
     $this->assertTrue(array_shift($children) == 'first', 'Child found in the correct order.');
     $this->assertTrue(array_shift($children) == 'second', 'Child found in the correct order.');