diff --git a/core/tests/Drupal/FunctionalJavascriptTests/Core/Session/SessionTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Core/Session/SessionTest.php
index e02e0df..fa2d541 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/Core/Session/SessionTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Core/Session/SessionTest.php
@@ -48,13 +48,10 @@ public function testSessionExpiration() {
     // number of times.
     $this->drupalGet('<front>');
 
-    $session_assert = $this->assertSession();
-
     $page = $this->getSession()->getPage();
 
     for ($i = 0; $i < 25; $i++) {
       $page->clickLink('Link to front page');
-      $session_assert->statusCodeEquals(200);
     }
   }
 
diff --git a/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
index 815a26b..0eddf94 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/JSWebAssert.php
@@ -366,4 +366,32 @@ function t(r, lx, ly) {
     return $this->session->evaluateScript($full_javascript_visibility_test);
   }
 
+  /**
+   * The use of statusCodeEquals() is not available in a functional JavaScript test.
+   *
+   * @throws \Exception
+   *   Throws an exception on use.
+   *
+   * @deprecated in Drupal 8.4.x, will be removed before Drupal 8.5.x. Use an
+   *             assertion on the DOM to validate what is expected. For example
+   *             assert that an element is available on the page.
+   */
+  public function statusCodeEquals($code) {
+    throw new \Exception('The use of statusCodeEquals() is not available in a functional JavaScript test.');
+  }
+
+  /**
+   * The use of statusCodeNotEquals() is not available in a functional JavaScript test.
+   *
+   * @throws \Exception
+   *   Throws an exception on use.
+   *
+   * @deprecated in Drupal 8.4.x, will be removed before Drupal 8.5.x. Use an
+   *             assertion on the DOM to validate what is expected. For example
+   *             assert that an element is not available on the page.
+   */
+  public function statusCodeNotEquals($code) {
+    throw new \Exception('The use of statusCodeNotEquals() is not available in a functional JavaScript test.');
+  }
+
 }
diff --git a/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
index d5156ee..807de75 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/JavascriptTestBase.php
@@ -2,6 +2,8 @@
 
 namespace Drupal\FunctionalJavascriptTests;
 
+use Drupal\Core\Session\AccountInterface;
+use Drupal\Core\Session\AnonymousUserSession;
 use Drupal\Tests\BrowserTestBase;
 use Zumba\GastonJS\Exception\DeadClient;
 use Zumba\Mink\Driver\PhantomJSDriver;
@@ -64,6 +66,44 @@ protected function tearDown() {
   }
 
   /**
+   * {@inheritdoc}
+   */
+  protected function drupalLogin(AccountInterface $account) {
+    if ($this->loggedInUser) {
+      $this->drupalLogout();
+    }
+
+    $this->drupalGet('user/login');
+    $page = $this->getSession()->getPage();
+    $page->fillField('name', $account->getAccountName());
+    $page->fillField('pass', $account->passRaw);
+    $page->findButton('Log in')->click();
+
+    $account->sessionId = $this->getSession()->getCookie($this->getSessionName());
+    $this->assertTrue($this->drupalUserIsLoggedIn($account));
+
+    $this->loggedInUser = $account;
+    $this->container->get('current_user')->setAccount($account);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function drupalLogout() {
+    // Make a request to the logout page, and redirect to the user page, the
+    // idea being if you were properly logged out you should be seeing a login
+    // screen.
+    $assert_session = $this->assertSession();
+    $this->drupalGet('user/logout', array('query' => array('destination' => 'user')));
+    $assert_session->fieldExists('name');
+    $assert_session->fieldExists('pass');
+    $this->assertFalse($this->loggedInUser);
+
+    $this->loggedInUser = FALSE;
+    $this->container->get('current_user')->setAccount(new AnonymousUserSession());
+  }
+
+  /**
    * Asserts that the element with the given CSS selector is visible.
    *
    * @param string $css_selector