diff -u b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
--- b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
@@ -370,6 +370,7 @@
    * The use of statusCodeEquals() is not available.
    *
    * @param int $code
+   *   The status code.
    *
    * @throws \Behat\Mink\Exception\UnsupportedDriverActionException
    *   Throws an exception on use.
@@ -382,6 +383,7 @@
    * The use of statusCodeNotEquals() is not available.
    *
    * @param int $code
+   *   The status code.
    *
    * @throws \Behat\Mink\Exception\UnsupportedDriverActionException
    *   Throws an exception on use.
@@ -394,7 +396,9 @@
    * The use of responseHeaderEquals() is not available.
    *
    * @param string $name
+   *   The name of the header.
    * @param string $value
+   *   The value to check the header against.
    *
    * @throws \Behat\Mink\Exception\UnsupportedDriverActionException
    *   Throws an exception on use.
@@ -407,13 +411,15 @@
    * The use of responseHeaderNotEquals() is not available.
    *
    * @param string $name
+   *   The name of the header.
    * @param string $value
+   *   The value to check the header against.
    *
    * @throws \Behat\Mink\Exception\UnsupportedDriverActionException
    *   Throws an exception on use.
    */
   public function responseHeaderNotEquals($name, $value) {
-    throw new UnsupportedDriverActionException('The use of responseHeaderEquals() is not available in a functional JavaScript test.');
+    throw new UnsupportedDriverActionException('The use of responseHeaderNotEquals() is not available in a functional JavaScript test.');
   }
 
 }