diff --git a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
index 95437fb..bc80fd8 100644
--- a/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Core\Cache\Cache;
 use Drupal\simpletest\WebTestBase;
+use Drupal\Component\Utility\String;
 
 /**
  * Provides testing for basic block module functionality.
@@ -190,12 +191,11 @@ function testThemeName() {
     // Explicitly set the default and admin themes.
     $theme = 'block_test_specialchars_theme';
     theme_enable(array($theme));
-    $this->resetAll();
     \Drupal::service('router.builder')->rebuild();
     $this->drupalGet('admin/structure/block');
-    $this->assertText('<"Cat" & 'Mouse'>');
+    $this->assertRaw(String::checkPlain('<"Cat" & \'Mouse\'>'));
     $this->drupalGet('admin/structure/block/list/block_test_specialchars_theme');
-    $this->assertLink('Demonstrate block regions (<"Cat" & \'Mouse\'>)');
+    $this->assertRaw(String::checkPlain('Demonstrate block regions (<"Cat" & \'Mouse\'>)'));
   }
 
   /**