only in patch2:
unchanged:
--- a/core/tests/Drupal/KernelTests/Core/Routing/ExceptionHandlingTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Routing/ExceptionHandlingTest.php
@@ -199,7 +199,7 @@ public function testExceptionEscaping() {
     // final exception subscriber, it is printed as partial HTML, and hence
     // escaped.
     $this->assertEqual('text/plain; charset=UTF-8', $response->headers->get('Content-type'));
-    $this->assertStringStartsWith('The website encountered an unexpected error. Please try again later.</br></br><em class="placeholder">Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException</em>: Not acceptable format: json&lt;script&gt;alert(123);&lt;/script&gt; in <em class="placeholder">', $response->getContent());
+    $this->assertStringStartsWith('The website encountered an unexpected error. Please try again later.<br /><br /><em class="placeholder">Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException</em>: Not acceptable format: json&lt;script&gt;alert(123);&lt;/script&gt; in <em class="placeholder">', $response->getContent());
   }
 
 }