diff --git a/core/lib/Drupal/Core/PathProcessor/PathProcessorAlias.php b/core/lib/Drupal/Core/PathProcessor/PathProcessorAlias.php
index 07e3a38..9e8400f 100644
--- a/core/lib/Drupal/Core/PathProcessor/PathProcessorAlias.php
+++ b/core/lib/Drupal/Core/PathProcessor/PathProcessorAlias.php
@@ -38,8 +38,8 @@ public function __construct(AliasManagerInterface $alias_manager) {
    * Implements Drupal\Core\PathProcessor\InboundPathProcessorInterface::processInbound().
    */
   public function processInbound($path, Request $request) {
-    $path = Unicode::strtolower($path);
-    return $this->aliasManager->getPathByAlias($path);
+    $path = $this->aliasManager->getPathByAlias($path);
+    return $path;
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Routing/RouteProvider.php b/core/lib/Drupal/Core/Routing/RouteProvider.php
index 8f98802..d9cf01b 100644
--- a/core/lib/Drupal/Core/Routing/RouteProvider.php
+++ b/core/lib/Drupal/Core/Routing/RouteProvider.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Core\Routing;
 
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Path\CurrentPathStack;
 use Drupal\Core\State\StateInterface;
 use Symfony\Cmf\Component\Routing\PagedRouteCollection;
@@ -258,7 +259,7 @@ public function getRoutesByPattern($pattern) {
   protected function getRoutesByPath($path) {
     // Filter out each empty value, though allow '0' and 0, which would be
     // filtered out by empty().
-    $parts = array_values(array_filter(explode('/', $path), function($value) {
+    $parts = array_values(array_filter(explode('/', Unicode::strtolower($path)), function($value) {
       return $value !== NULL && $value !== '';
     }));