diff -u b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
--- b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
+++ b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
@@ -430,8 +430,7 @@
   protected function assertNoFieldById($id, $value = '') {
     $field = $this->getSession()->getPage()->findById($id);
 
-    // Manual test instead of assertNull() to keep the thrown exception the
-    // same.
+    // Return early if the field could not be found as expected.
     if ($field === NULL) {
       return;
     }
@@ -439,8 +438,6 @@
     if (!isset($value)) {
       throw new ExpectationException(sprintf('Id "%s" appears on this page, but it should not.', $id), $this->getSession()->getDriver());
     }
-    // Manual test instead of assertEquals() to keep the thrown exception the
-    // same.
     elseif ($value === $field->getValue()) {
       throw new ExpectationException(sprintf('Failed asserting that %s is not equal to %s', $field->getValue(), $value), $this->getSession()->getDriver());
     }