diff --git a/core/modules/views_ui/lib/Drupal/views_ui/Tests/PreviewTest.php b/core/modules/views_ui/lib/Drupal/views_ui/Tests/PreviewTest.php
index 46ec2e4..77cc434 100644
--- a/core/modules/views_ui/lib/Drupal/views_ui/Tests/PreviewTest.php
+++ b/core/modules/views_ui/lib/Drupal/views_ui/Tests/PreviewTest.php
@@ -7,8 +7,6 @@
 
 namespace Drupal\views_ui\Tests;
 
-use Drupal\Component\Utility\String;
-
 /**
  * Tests the preview form in the UI.
  */
@@ -92,7 +90,8 @@ function testPreviewUI() {
     $this->drupalPostForm('admin/structure/views/add', $view, t('Save and edit'));
     $this->clickLink(t('Feed'));
     $this->drupalPostForm(NULL, array(), t('Update preview'));
-    $this->assertText(String::checkPlain('<title>' . $view['page[title]'] . '</title>'), 'The Feed RSS preview was rendered.');
+    $result = $this->xpath('//div[@id="views-live-preview"]/pre');
+    $this->assertTrue(strpos($result[0], '<title>' . $view['page[title]'] . '</title>'), 'The Feed RSS preview was rendered.');
   }
 
   /**