diff --git a/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionHtmlSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionHtmlSubscriber.php
index b6b2b09..38cb895 100644
--- a/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionHtmlSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionHtmlSubscriber.php
@@ -137,12 +137,9 @@ protected function makeSubrequest(GetResponseForExceptionEvent $event, $url, $st
       // The routing to the 404 page should be done as GET request because it is
       // restricted to GET and POST requests only. Otherwise a DELETE request
       // would for example trigger a method not allowed exception.
-      $original_request_context = $this->accessUnawareRouter->getContext();
-      if ($original_request_context) {
-        $request_context = clone $original_request_context;
-        $request_context->setMethod('GET');
-        $this->accessUnawareRouter->setContext($request_context);
-      }
+      $request_context = clone ($this->accessUnawareRouter->getContext());
+      $request_context->setMethod('GET');
+      $this->accessUnawareRouter->setContext($request_context);
 
       $sub_request->attributes->add($this->accessUnawareRouter->match($url));
 
diff --git a/core/tests/Drupal/Tests/Core/EventSubscriber/CustomPageExceptionHtmlSubscriberTest.php b/core/tests/Drupal/Tests/Core/EventSubscriber/CustomPageExceptionHtmlSubscriberTest.php
index 5d3993d..81e7cc6 100644
--- a/core/tests/Drupal/Tests/Core/EventSubscriber/CustomPageExceptionHtmlSubscriberTest.php
+++ b/core/tests/Drupal/Tests/Core/EventSubscriber/CustomPageExceptionHtmlSubscriberTest.php
@@ -14,6 +14,7 @@
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+use Symfony\Component\Routing\RequestContext;
 
 /**
  * @coversDefaultClass \Drupal\Core\EventSubscriber\CustomPageExceptionHtmlSubscriber
@@ -127,6 +128,12 @@ protected function tearDown() {
   public function testHandleWithPostRequest() {
     $request = Request::create('/test', 'POST', array('name' => 'druplicon', 'pass' => '12345'));
 
+    $request_context = new RequestContext();
+    $request_context->fromRequest($request);
+    $this->accessUnawareRouter->expects($this->any())
+      ->method('getContext')
+      ->willReturn($request_context);
+
     $this->kernel->expects($this->once())->method('handle')->will($this->returnCallback(function (Request $request) {
       return new HtmlResponse($request->getMethod());
     }));
@@ -148,6 +155,12 @@ public function testHandleWithGetRequest() {
     $request = Request::create('/test', 'GET', array('name' => 'druplicon', 'pass' => '12345'));
     $request->attributes->set(AccessAwareRouterInterface::ACCESS_RESULT, AccessResult::forbidden()->addCacheTags(['druplicon']));
 
+    $request_context = new RequestContext();
+    $request_context->fromRequest($request);
+    $this->accessUnawareRouter->expects($this->any())
+      ->method('getContext')
+      ->willReturn($request_context);
+
     $this->kernel->expects($this->once())->method('handle')->will($this->returnCallback(function (Request $request) {
       return new Response($request->getMethod() . ' ' . UrlHelper::buildQuery($request->query->all()));
     }));