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
@@ -30,14 +30,14 @@
   public function assertWaitOnAjaxRequest($timeout = 10000, $message = 'Unable to complete AJAX request.') {
     $condition = <<<JS
       (function() {
-        function isNotAjaxing(instance) {
-          return instance ? !instance.ajaxing : true;
+        function isAjaxing(instance) {
+          return instance && instance.ajaxing === true;
         }
         return (
           // Assert no AJAX request is running (via jQuery or Drupal) and no
           // animation is running.
           (typeof jQuery === 'undefined' || (jQuery.active === 0 && jQuery(':animated').length === 0)) &&
-          (typeof Drupal === 'undefined' || typeof Drupal.ajax === 'undefined' || !Drupal.ajax.instances.every(isNotAjaxing))
+          (typeof Drupal === 'undefined' || typeof Drupal.ajax === 'undefined' || !Drupal.ajax.instances.some(isAjaxing))
         );
       }());
 JS;
@@ -93,8 +93,9 @@
     $page = $this->session->getPage();
 
     $result = $page->waitFor($timeout, function() use ($page, $selector, $locator) {
-      if($element = $page->find($selector, $locator)) {
-        return $element->isVisible();
+      $element = $page->find($selector, $locator);
+      if (!empty($element) && $element->isVisible()) {
+        return $element;
       }
       return null;
     });
@@ -107,12 +108,14 @@
    *
    * @param string $locator
    *   The button ID, value or alt string.
+   * @param int $timeout
+   *   (Optional) Timeout in milliseconds, defaults to 10000.
    *
    * @return \Behat\Mink\Element\NodeElement|null
    *   The page element node if found, NULL if not.
    */
-  public function waitForButton($locator) {
-    return $this->waitForElement('named', array('button', $locator));
+  public function waitForButton($locator, $timeout = 10000) {
+    return $this->waitForElement('named', array('button', $locator), $timeout);
   }
 
   /**
@@ -120,12 +123,14 @@
    *
    * @param string $locator
    *   The link ID, title, text or image alt.
+   * @param int $timeout
+   *   (Optional) Timeout in milliseconds, defaults to 10000.
    *
    * @return \Behat\Mink\Element\NodeElement|null
    *   The page element node if found, NULL if not.
    */
-  public function waitForLink($locator) {
-    return $this->waitForElement('named', array('link', $locator));
+  public function waitForLink($locator, $timeout = 10000) {
+    return $this->waitForElement('named', array('link', $locator), $timeout);
   }
 
   /**
@@ -133,12 +138,14 @@
    *
    * @param string $locator
    *   The input ID, name or label for the field (input, textarea, select).
+   * @param int $timeout
+   *   (Optional) Timeout in milliseconds, defaults to 10000.
    *
    * @return \Behat\Mink\Element\NodeElement|null
    *   The page element node if found, NULL if not.
    */
-  public function waitForField($locator) {
-    return $this->waitForElement('named', array('field', $locator));
+  public function waitForField($locator, $timeout = 10000) {
+    return $this->waitForElement('named', array('field', $locator), $timeout);
   }
 
   /**
@@ -146,12 +153,14 @@
    *
    * @param string $id
    *   The element ID.
+   * @param int $timeout
+   *   (Optional) Timeout in milliseconds, defaults to 10000.
    *
    * @return \Behat\Mink\Element\NodeElement|null
    *   The page element node if found, NULL if not.
    */
-  public function waitForId($id) {
-    return $this->waitForElement('named', array('id', $id));
+  public function waitForId($id, $timeout = 10000) {
+    return $this->waitForElement('named', array('id', $id), $timeout);
   }
 
   /**
diff -u b/core/tests/Drupal/FunctionalJavascriptTests/Tests/JSWebAssertTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Tests/JSWebAssertTest.php
--- b/core/tests/Drupal/FunctionalJavascriptTests/Tests/JSWebAssertTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Tests/JSWebAssertTest.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\FunctionalJavascriptTests\Tests;
 
+use Behat\Mink\Element\NodeElement;
 use Drupal\FunctionalJavascriptTests\JavascriptTestBase;
 
 /**
@@ -37,45 +38,51 @@
 
     // Test the wait...() methods by first checking the fields aren't available
     // and then are available after the wait method.
-    $test_button->click();
     $result = $page->findButton('Added button');
     $this->assertEmpty($result);
+    $test_button->click();
     $result = $assert_session->waitForButton('Added button');
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
 
-    $test_link->click();
     $result = $page->findLink('Added link');
     $this->assertEmpty($result);
+    $test_link->click();
     $result = $assert_session->waitForLink('Added link');
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
 
-    $test_field->click();
     $result = $page->findField('added_field');
     $this->assertEmpty($result);
+    $test_field->click();
     $result = $assert_session->waitForField('added_field');
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
 
-    $test_id->click();
     $result = $page->findById('js_webassert_test_field_id');
     $this->assertEmpty($result);
+    $test_id->click();
     $result = $assert_session->waitForId('js_webassert_test_field_id');
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
 
     // Test waitOnAjaxRequest. Verify the element is available after the wait
     // and the behaviors have run on completing by checking the value.
-    $test_wait_on_ajax->click();
     $result = $page->findField('test_assert_wait_on_ajax_input');
     $this->assertEmpty($result);
+    $test_wait_on_ajax->click();
     $assert_session->assertWaitOnAjaxRequest();
     $result = $page->findField('test_assert_wait_on_ajax_input');
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
     $this->assertEquals('js_webassert_test', $result->getValue());
 
-    $test_wait_on_element_visible->click();
     $result = $page->findButton('Added WaitForElementVisible');
     $this->assertEmpty($result);
+    $test_wait_on_element_visible->click();
     $result = $assert_session->waitForElementVisible('named', array('button', 'Added WaitForElementVisible'));
     $this->assertNotEmpty($result);
+    $this->assertTrue($result instanceof NodeElement);
     $this->assertEquals(TRUE, $result->isVisible());
   }
 
only in patch2:
unchanged:
--- a/core/tests/Drupal/FunctionalJavascriptTests/EntityReference/EntityReferenceAutocompleteWidgetTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/EntityReference/EntityReferenceAutocompleteWidgetTest.php
@@ -88,7 +88,7 @@ public function testEntityReferenceAutocompleteWidget() {
     $page = $this->getSession()->getPage();
 
     $autocomplete_field = $page->findField($field_name . '[0][target_id]');
-    $autocomplete_field->setValue('Test');
+    $autocomplete_field->setValue('Test page');
     $this->getSession()->getDriver()->keyDown($autocomplete_field->getXpath(), ' ');
     $assert_session->waitOnAutocomplete();