diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index b7dfd3a931641cf7b1288a3d349a52c26ebe1508..7361a82d91df2e59961ecb3d71c26602e25f4b24 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -7,15 +7,9 @@
 
 namespace Drupal\Core;
 
-use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\HttpFoundation\Response;
-use Symfony\Component\Routing\RequestContext;
 use Symfony\Component\HttpKernel\HttpKernel;
-use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
-use Symfony\Component\EventDispatcher\Event;
 use Symfony\Component\HttpKernel\Controller\ControllerResolverInterface;
-use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
 use Symfony\Component\HttpKernel\EventListener\ExceptionListener;
 use Drupal\Core\EventSubscriber\ViewSubscriber;
 use Drupal\Core\EventSubscriber\AccessSubscriber;
@@ -27,8 +21,6 @@
 use Drupal\Core\EventSubscriber\RequestCloseSubscriber;
 use Drupal\Core\EventSubscriber\RouterListener;
 
-use Exception;
-
 /**
  * The DrupalKernel class is the core of Drupal itself.
  */
diff --git a/core/lib/Drupal/Core/EventSubscriber/AccessSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/AccessSubscriber.php
index 4d10489ce6f9d939dc4f942b5052fa0d2ffc032a..4f1dc7545dff73f9754150e5b3a4239d7c5f1c02 100644
--- a/core/lib/Drupal/Core/EventSubscriber/AccessSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/AccessSubscriber.php
@@ -7,13 +7,9 @@
 
 namespace Drupal\Core\EventSubscriber;
 
-use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
-use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
-use Symfony\Component\Routing\Exception\ResourceNotFoundException;
-use Symfony\Component\Routing\Exception\MethodNotAllowedException;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 /**
diff --git a/core/lib/Drupal/Core/EventSubscriber/LegacyControllerSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/LegacyControllerSubscriber.php
index 48cc8a0c542dabcdcff56f991d5991d11a50dac1..f088f7ef2e2e7373761dd317e7bdefe406d6ccba 100644
--- a/core/lib/Drupal/Core/EventSubscriber/LegacyControllerSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/LegacyControllerSubscriber.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\EventSubscriber;
 
-use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\FilterControllerEvent;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
diff --git a/core/lib/Drupal/Core/EventSubscriber/LegacyRequestSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/LegacyRequestSubscriber.php
index 84365a577ad216432070fd2b1d18f6bdbd687c03..242f9352cc455b7e2849cbbc6a3c2d71d6d59650 100644
--- a/core/lib/Drupal/Core/EventSubscriber/LegacyRequestSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/LegacyRequestSubscriber.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\EventSubscriber;
 
-use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
diff --git a/core/lib/Drupal/Core/EventSubscriber/PathSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/PathSubscriber.php
index 1e2a95a34bccafdb4efd102f0612ba8eba272b2b..910454438cae5557213fdc06fd4683c7784b194f 100644
--- a/core/lib/Drupal/Core/EventSubscriber/PathSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/PathSubscriber.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\Core\EventSubscriber;
 
-use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
diff --git a/core/lib/Drupal/Core/EventSubscriber/RouterListener.php b/core/lib/Drupal/Core/EventSubscriber/RouterListener.php
index c7e13a2bffcfff0977663a0d5c5d53bb4f978e47..7b158fdf5f656cca04f9d977b1a7afd77db8b32a 100644
--- a/core/lib/Drupal/Core/EventSubscriber/RouterListener.php
+++ b/core/lib/Drupal/Core/EventSubscriber/RouterListener.php
@@ -15,7 +15,6 @@
 use Symfony\Component\HttpKernel\Log\LoggerInterface;
 use Symfony\Component\Routing\Matcher\UrlMatcherInterface;
 use Symfony\Component\Routing\Exception\ResourceNotFoundException;
-use Symfony\Component\Routing\Exception\MethodNotFoundException;
 
 /**
  * Drupal-specific Router listener.
diff --git a/core/lib/Drupal/Core/EventSubscriber/ViewSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/ViewSubscriber.php
index 4c6bde214240d9f184a0db84845d749b5d42ae2d..120ac7be1bef8a4916cdb12c79a725bb7e3ab391 100644
--- a/core/lib/Drupal/Core/EventSubscriber/ViewSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/ViewSubscriber.php
@@ -11,10 +11,6 @@
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
-use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
-use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
-use Symfony\Component\Routing\Exception\ResourceNotFoundException;
-use Symfony\Component\Routing\Exception\MethodNotAllowedException;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 use Drupal\Core\ContentNegotiation;
diff --git a/core/lib/Drupal/Core/ExceptionController.php b/core/lib/Drupal/Core/ExceptionController.php
index a2ab913c106967dd50d4cac8b2d389e737412959..b1633950411025023ee8fcee6113ef6a184fd4c5 100644
--- a/core/lib/Drupal/Core/ExceptionController.php
+++ b/core/lib/Drupal/Core/ExceptionController.php
@@ -10,14 +10,9 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpFoundation\JsonResponse;
-
 use Symfony\Component\HttpKernel\HttpKernelInterface;
-use Symfony\Component\EventDispatcher\EventDispatcher;
-use Symfony\Component\HttpKernel\Controller\ControllerResolver;
 use Symfony\Component\HttpKernel\Exception\FlattenException;
 
-use Exception;
-
 /**
  * This controller handles HTTP errors generated by the routing system.
  */
diff --git a/core/lib/Drupal/Core/LegacyUrlMatcher.php b/core/lib/Drupal/Core/LegacyUrlMatcher.php
index 1ea0c5dcc133e93fa5305cdfe89760f145008b12..8828f36d27b4438d6ac587159aef9dba4499ab67 100644
--- a/core/lib/Drupal/Core/LegacyUrlMatcher.php
+++ b/core/lib/Drupal/Core/LegacyUrlMatcher.php
@@ -8,13 +8,9 @@
 namespace Drupal\Core;
 
 use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\Routing\Exception\MethodNotAllowedException;
 use Symfony\Component\Routing\Exception\ResourceNotFoundException;
 use Symfony\Component\Routing\Matcher\UrlMatcherInterface;
-use Symfony\Component\Routing\Matcher\UrlMatcher as SymfonyUrlMatcher;
 use Symfony\Component\Routing\RequestContext;
-use Symfony\Component\Routing\Route;
-use Symfony\Component\Routing\RouteCollection;
 
 /**
  * UrlMatcher matches URL based on a set of routes.