diff --git a/core/lib/Drupal/Core/Routing/CompiledRoute.php b/core/lib/Drupal/Core/Routing/CompiledRoute.php
index 2e2ff6b..ef7ca47 100644
--- a/core/lib/Drupal/Core/Routing/CompiledRoute.php
+++ b/core/lib/Drupal/Core/Routing/CompiledRoute.php
@@ -56,7 +56,8 @@ class CompiledRoute extends SymfonyCompiledRoute {
    * @param array $tokens
    *   An array of tokens to use to generate URL for this route
    * @param array $pathVariables
-   *   An array of path variables
+   *   An array of path variable names where the numeric array keys correspond
+   *   to the path part where the named variable is found in the path pattern.
    * @param string|null $hostRegex
    *   Host regex
    * @param array $hostTokens
@@ -143,6 +144,27 @@ public function getRequirements() {
   }
 
   /**
+   * Returns the path variables.
+   *
+   * The Drupal implementation differs from the parent class in that the numeric
+   * array keys correspond to a matching path part containing that variable.
+   * For example, for a route with path
+   * @code
+   * /node/{node}/revisions/{node_revision}/view
+   * @endcode
+   * this method will return the array
+   * @code
+   * [1 => 'node', 3 => 'node_revision']
+   * @endcode
+   *
+   * @return array
+   *   The path variable names keyed by numeric path part.
+   */
+  public function getPathVariables() {
+    return parent::getPathVariables();
+  }
+
+  /**
    * {@inheritdoc}
    */
   public function serialize() {
diff --git a/core/lib/Drupal/Core/Routing/RouteBuilder.php b/core/lib/Drupal/Core/Routing/RouteBuilder.php
index a78cf0c..c88a033 100644
--- a/core/lib/Drupal/Core/Routing/RouteBuilder.php
+++ b/core/lib/Drupal/Core/Routing/RouteBuilder.php
@@ -8,6 +8,7 @@
 namespace Drupal\Core\Routing;
 
 use Drupal\Component\Discovery\YamlDiscovery;
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Access\CheckProviderInterface;
 use Drupal\Core\Controller\ControllerResolverInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
@@ -174,7 +175,9 @@ public function rebuild() {
           'condition' => '',
         );
 
-        $route = new Route($route_info['path'], $route_info['defaults'], $route_info['requirements'], $route_info['options'], $route_info['host'], $route_info['schemes'], $route_info['methods'], $route_info['condition']);
+        // Lowercase the path here so that the events get a consistent path,
+        // even though we force them all to be lowercase later.
+        $route = new Route(Unicode::strtolower($route_info['path']), $route_info['defaults'], $route_info['requirements'], $route_info['options'], $route_info['host'], $route_info['schemes'], $route_info['methods'], $route_info['condition']);
         $collection->add($name, $route);
       }
     }
@@ -182,11 +185,15 @@ public function rebuild() {
     // DYNAMIC is supposed to be used to add new routes based upon all the
     // static defined ones.
     $this->dispatcher->dispatch(RoutingEvents::DYNAMIC, new RouteBuildEvent($collection));
+    // Process the whole collection since we cannot tell what was newly added.
+    $this->lowercaseCollection($collection);
 
     // ALTER is the final step to alter all the existing routes. We cannot stop
     // people from adding new routes here, but we define two separate steps to
     // make it clear.
     $this->dispatcher->dispatch(RoutingEvents::ALTER, new RouteBuildEvent($collection));
+    // Process the whole collection since we cannot tell what was changed.
+    $this->lowercaseCollection($collection);
 
     $this->checkProvider->setChecks($collection);
 
@@ -223,6 +230,20 @@ public function destruct() {
   }
 
   /**
+   * Lowercases the path for each route in the collection.
+   *
+   * @param \Symfony\Component\Routing\RouteCollection $collection
+   *   A route collection.
+   */
+  protected function lowercaseCollection(RouteCollection $collection) {
+    foreach ($collection->all() as $route) {
+      // Force each path to be lowercase.
+      $path = Unicode::strtolower($route->getPath());
+      $route->setPath($path);
+    }
+  }
+
+  /**
    * Retrieves all defined routes from .routing.yml files.
    *
    * @return array
diff --git a/core/lib/Drupal/Core/Routing/RouteCompiler.php b/core/lib/Drupal/Core/Routing/RouteCompiler.php
index 639feff..ece32e2 100644
--- a/core/lib/Drupal/Core/Routing/RouteCompiler.php
+++ b/core/lib/Drupal/Core/Routing/RouteCompiler.php
@@ -55,7 +55,7 @@ public static function compile(Route $route) {
       $symfony_compiled->getStaticPrefix(),
       $symfony_compiled->getRegex(),
       $symfony_compiled->getTokens(),
-      $symfony_compiled->getPathVariables(),
+      static::getMappedPathVariables($route->getPath(), $symfony_compiled->getPathVariables()),
       $symfony_compiled->getHostRegex(),
       $symfony_compiled->getHostTokens(),
       $symfony_compiled->getHostVariables(),
@@ -64,6 +64,36 @@ public static function compile(Route $route) {
   }
 
   /**
+   * Returns the mapping of route variables to numeric path part.
+   *
+   * Drupal only supports path wildcard (variables) that consist of a complete
+   * part of the path separated by slashes.
+   *
+   * @see \Symfony\Component\Routing\RouteCompiler::compilePattern()
+   *
+   * @param string $path
+   *   The path for which we want the mapping.
+   * @param array $variables
+   *   The names of placeholder variables in the path.
+   *
+   * @return array
+   *   The mapping of numeric path part to variable name.
+   */
+  public static function getMappedPathVariables($path, array $variables) {
+    $map = [];
+    // Split the path up on the slashes, ignoring multiple slashes in a row
+    // or leading or trailing slashes.
+    $parts = preg_split('@/+@', $path, NULL, PREG_SPLIT_NO_EMPTY);
+    foreach ($variables as $name) {
+      $index = array_search('{' . $name . '}', $parts, TRUE);
+      if ($index !== FALSE) {
+        $map[$index] = $name;
+      }
+    }
+    return $map;
+  }
+
+  /**
    * Returns the pattern outline.
    *
    * The pattern outline is the path pattern but normalized so that all
diff --git a/core/lib/Drupal/Core/Routing/RouteProvider.php b/core/lib/Drupal/Core/Routing/RouteProvider.php
index 937cff7..783b6ca 100644
--- a/core/lib/Drupal/Core/Routing/RouteProvider.php
+++ b/core/lib/Drupal/Core/Routing/RouteProvider.php
@@ -10,6 +10,7 @@
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\Cache\CacheTagsInvalidatorInterface;
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Path\CurrentPathStack;
 use Drupal\Core\PathProcessor\InboundPathProcessorInterface;
 use Drupal\Core\State\StateInterface;
@@ -147,7 +148,9 @@ public function __construct(Connection $connection, StateInterface $state, Curre
    */
   public function getRouteCollectionForRequest(Request $request) {
     // Cache both the system path as well as route parameters and matching
-    // routes.
+    // routes. We can not yet convert the path to lowercase since wildcard path
+    // portions may be case sensitive if they contain data like a base64 encoded
+    // token.
     $cid = 'route:' . $request->getPathInfo() . ':' .  $request->getQueryString();
     if ($cached = $this->cache->get($cid)) {
       $this->currentPath->setPath($cached->data['path'], $request);
@@ -155,9 +158,9 @@ public function getRouteCollectionForRequest(Request $request) {
       return $cached->data['routes'];
     }
     else {
-      // Just trim on the right side.
       $path = $request->getPathInfo();
-      $path = $path === '/' ? $path : rtrim($request->getPathInfo(), '/');
+      // Just trim path on the right side.
+      $path = $path === '/' ? $path : rtrim($path, '/');
       $path = $this->pathProcessor->processInbound($path, $request);
       $this->currentPath->setPath($path, $request);
       // Incoming path processors may also set query parameters.
@@ -314,10 +317,12 @@ public function getRoutesByPattern($pattern) {
   }
 
   /**
-   * Get all routes which match a certain pattern.
+   * Get all routes which match a certain path pattern.
+   *
+   * The path will be converted to lowercase before performing the match.
    *
    * @param string $path
-   *   The route pattern to search for (contains % as placeholders).
+   *   The route path pattern to search for (contains % as placeholders).
    *
    * @return \Symfony\Component\Routing\RouteCollection
    *   Returns a route collection of matching routes.
@@ -325,7 +330,7 @@ public function getRoutesByPattern($pattern) {
   protected function getRoutesByPath($path) {
     // Split the path up on the slashes, ignoring multiple slashes in a row
     // or leading or trailing slashes.
-    $parts = preg_split('@/+@', $path, NULL, PREG_SPLIT_NO_EMPTY);
+    $parts = preg_split('@/+@', Unicode::strtolower($path), NULL, PREG_SPLIT_NO_EMPTY);
 
     $collection = new RouteCollection();
 
diff --git a/core/lib/Drupal/Core/Routing/UrlMatcher.php b/core/lib/Drupal/Core/Routing/UrlMatcher.php
index 49bff8f..f802d2f 100644
--- a/core/lib/Drupal/Core/Routing/UrlMatcher.php
+++ b/core/lib/Drupal/Core/Routing/UrlMatcher.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Core\Routing;
 
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Path\CurrentPathStack;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\Routing\RouteCollection;
@@ -46,4 +47,83 @@ public function finalMatch(RouteCollection $collection, Request $request) {
     return $this->match($this->currentPath->getPath($request));
   }
 
+  /**
+   * Tries to match a URL with a set of routes.
+   *
+   * This version differs from the Symfony parent version in two respects.
+   * First, the $pathinfo string is converted to lowercase when matching the
+   * route path regular expression. In addition, we remove the check against any
+   * static prefix since we would already have matched the static prefix in
+   * \Drupal\Core\Routing\RouteProvider before arriving here.
+   *
+   * @param string $pathinfo
+   *   The path to be parsed.
+   * @param \Symfony\Component\Routing\RouteCollection $routes
+   *   The set of routes.
+   *
+   * @return array
+   *   An array of route parameters.
+   *
+   * @throws \Symfony\Component\Routing\Exception\ResourceNotFoundException
+   *   If the resource could not be found.
+   * @throws \Symfony\Component\Routing\Exception\MethodNotAllowedException
+   *   If the resource was found but the request method is not allowed.
+   */
+  protected function matchCollection($pathinfo, RouteCollection $routes) {
+    foreach ($routes as $name => $route) {
+      /** @var \Symfony\Component\Routing\Route $route */
+      $compiledRoute = $route->compile();
+
+      // Convert the path to lowercase, so that we match the patterns from
+      // routes where we forced all paths to be lowercase.
+      // @see \Drupal\Core\Routing\RouteBuilder::rebuild()
+      // @see \Drupal\Core\Routing\RouteProvider::getRoutesByPath()
+      if (!preg_match($compiledRoute->getRegex(), Unicode::strtolower($pathinfo), $matches)) {
+        continue;
+      }
+      // Recover the original value for wildcard (named variable) portions
+      // of the path, since they may be case-sensitive data like a base64
+      // encoded token. We create this positional mapping in the route compiler.
+      // @see \Drupal\Core\Routing\RouteCompiler::getMappedPathVariables()
+      $parts = preg_split('@/+@', $pathinfo, NULL, PREG_SPLIT_NO_EMPTY);
+      foreach ($compiledRoute->getPathVariables() as $position => $variable_name) {
+        if (isset($matches[$variable_name])) {
+          $matches[$variable_name] = $parts[$position];
+        }
+      }
+
+      $hostMatches = array();
+      if ($compiledRoute->getHostRegex() && !preg_match($compiledRoute->getHostRegex(), $this->context->getHost(), $hostMatches)) {
+        continue;
+      }
+
+      // Check the HTTP method requirement.
+      if ($requiredMethods = $route->getMethods()) {
+        // HEAD and GET are equivalent as per RFC.
+        $method = $this->context->getMethod();
+        if ('HEAD' === $method) {
+          $method = 'GET';
+        }
+
+        if (!in_array($method, $requiredMethods)) {
+          $this->allow = array_merge($this->allow, $requiredMethods);
+
+          continue;
+        }
+      }
+
+      $status = $this->handleRouteRequirements($pathinfo, $name, $route);
+
+      if (self::ROUTE_MATCH === $status[0]) {
+        return $status[1];
+      }
+
+      if (self::REQUIREMENT_MISMATCH === $status[0]) {
+        continue;
+      }
+
+      return $this->getAttributes($route, $name, array_replace($matches, $hostMatches));
+    }
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Routing/routing.api.php b/core/lib/Drupal/Core/Routing/routing.api.php
index 7c5e80a..f5a38e3 100644
--- a/core/lib/Drupal/Core/Routing/routing.api.php
+++ b/core/lib/Drupal/Core/Routing/routing.api.php
@@ -43,7 +43,7 @@
  *   by the machine name of the module that defines the route, or the name of
  *   a subsystem.
  * - The 'path' line gives the URL path of the route (relative to the site's
- *   base URL).
+ *   base URL). Paths are handled with case-insensitive matching.
  * - The 'defaults' section tells how to build the main content of the route,
  *   and can also give other information, such as the page title and additional
  *   arguments for the route controller method. There are several possibilities
diff --git a/core/modules/config_translation/src/Tests/ConfigTranslationOverviewTest.php b/core/modules/config_translation/src/Tests/ConfigTranslationOverviewTest.php
index 13b56d5..387aeaa 100644
--- a/core/modules/config_translation/src/Tests/ConfigTranslationOverviewTest.php
+++ b/core/modules/config_translation/src/Tests/ConfigTranslationOverviewTest.php
@@ -8,6 +8,7 @@
 namespace Drupal\config_translation\Tests;
 
 use Drupal\Component\Utility\Html;
+use Drupal\Component\Utility\Unicode;
 use Drupal\language\Entity\ConfigurableLanguage;
 use Drupal\simpletest\WebTestBase;
 
@@ -96,7 +97,7 @@ public function testMapperListPage() {
 
     foreach ($labels as $label) {
       $test_entity = entity_create('config_test', array(
-        'id' => $this->randomMachineName(),
+        'id' => Unicode::strtolower($this->randomMachineName()),
         'label' => $label,
       ));
       $test_entity->save();
diff --git a/core/modules/system/src/Tests/Menu/MenuRouterTest.php b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
index 42332e0..68b6657 100644
--- a/core/modules/system/src/Tests/Menu/MenuRouterTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\system\Tests\Menu;
 
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Url;
 use Drupal\simpletest\WebTestBase;
 
diff --git a/core/modules/system/src/Tests/Routing/RouterTest.php b/core/modules/system/src/Tests/Routing/RouterTest.php
index 17345fa..06a5119 100644
--- a/core/modules/system/src/Tests/Routing/RouterTest.php
+++ b/core/modules/system/src/Tests/Routing/RouterTest.php
@@ -211,6 +211,71 @@ public function testRouterMatching() {
   }
 
   /**
+   * Tests the case insensitivity of route paths and path variable handling.
+   *
+   * The un-routed URLs are constructed using base: so that we are sure they are
+   * used as written without being processed by the routing system.
+   */
+  public function testRoutePathMixedCase() {
+    $this->drupalGet(Url::fromUri('base:router_test/TEST14/1'));
+    $this->assertResponse(200);
+    $this->assertText('User route "entity.user.canonical" was matched.');
+
+    /** @var \Drupal\Core\Routing\RouteProvider $route_provider */
+    $route_provider = $this->container->get('router.route_provider');
+    $route2 = $route_provider->getRouteByName('router_test.mixedcase.2');
+    // Verify that the route path is stored as lowercase despite being defined
+    // with mixed case in the YAML file.
+    $this->assertIdentical('/router_test/mixedcase2', $route2->getPath());
+    $this->drupalGet(Url::fromUri('base:router_test/mixEDCASE2'));
+    $this->assertResponse(200);
+    $this->assertRaw('test2', 'The expected controller output was found.');
+
+    $this->drupalGet(Url::fromUri('base:router_TEST/MIXEDcase2'));
+    $this->assertResponse(200);
+    $this->assertRaw('test2', 'The expected controller output was found.');
+
+    $this->drupalGet(Url::fromUri('base:router_test/mixedcase2'));
+    $this->assertResponse(200);
+    $this->assertRaw('test2', 'The expected controller output was found.');
+
+    $route3 = $route_provider->getRouteByName('router_test.mixedcase.3');
+    // Verify that the variable name in the route path is stored as lowercase
+    // despite being defined with mixed case in the YAML file.
+    $this->assertIdentical('/router_test/mixedcase3/{value}', $route3->getPath());
+
+    // Verify that data in variable path parts is retained as the original,
+    // mixed-case value. Matches route path /router_test/mixedcase3/{value}
+    $this->drupalGet(Url::fromUri('base:router_test/mixedcase3/mixedCASEstring'));
+    $this->assertResponse(200);
+    $this->assertRaw('mixedCASEstring', 'The variable string was output with unmodified case.');
+
+    $this->drupalGet(Url::fromUri('base:router_test/mixedcase3/mixedcasestring'));
+    $this->assertResponse(200);
+    $this->assertRaw('mixedcasestring', 'The variable string was output with unmodified case.');
+
+    $this->drupalGet(Url::fromUri('base:router_test/mixedcase3/MIXEDCASESTRING'));
+    $this->assertResponse(200);
+    $this->assertRaw('MIXEDCASESTRING', 'The variable string was output with unmodified case.');
+    // Test routes added by \Drupal\router_test\RouteTestSubscriber.
+    // Check that a dynamically added route has path changed to lower-case.
+    $route4 = $route_provider->getRouteByName('router_test.mixedcase.4');
+    $this->assertIdentical('/router_test/mixedcase4', $route4->getPath());
+    $this->drupalGet(Url::fromUri('base:router_TEST/MixedCASE4'));
+    $this->assertResponse(200);
+    // Check that a route added dynamically and altered has path lower-cased.
+    $route5 = $route_provider->getRouteByName('router_test.mixedcase.5');
+    $this->assertIdentical('/router_test/mixedcase5/altered', $route5->getPath());
+    $this->drupalGet(Url::fromUri('base:router_test/MixedCASE5/altereD'));
+    $this->assertResponse(200);
+    // Check that a route added during the alter event has path lower-cased.
+    $route6 = $route_provider->getRouteByName('router_test.mixedcase.6');
+    $this->assertIdentical('/router_test/mixedcase6', $route6->getPath());
+    $this->drupalGet(Url::fromUri('base:router_test/MixedCASE6'));
+    $this->assertResponse(200);
+  }
+
+  /**
    * Tests that a PSR-7 response works.
    */
   public function testRouterResponsePsr7() {
diff --git a/core/modules/system/tests/modules/router_test_directory/router_test.routing.yml b/core/modules/system/tests/modules/router_test_directory/router_test.routing.yml
index e0c91dd..7bf05b7 100644
--- a/core/modules/system/tests/modules/router_test_directory/router_test.routing.yml
+++ b/core/modules/system/tests/modules/router_test_directory/router_test.routing.yml
@@ -189,3 +189,17 @@ router_test.hierarchy_parent_child2:
     _controller: '\Drupal\router_test\TestControllers::test'
   requirements:
     _access: 'TRUE'
+
+router_test.mixedcase.2:
+  path: '/router_test/mixedCASE2'
+  defaults:
+    _controller: '\Drupal\router_test\TestControllers::test2'
+  requirements:
+    _access: 'TRUE'
+
+router_test.mixedcase.3:
+    path: '/router_test/mixedcase3/{ValUe}'
+    defaults:
+      _controller: '\Drupal\router_test\TestControllers::test3'
+    requirements:
+      _access: 'TRUE'
diff --git a/core/modules/system/tests/modules/router_test_directory/src/RouteTestSubscriber.php b/core/modules/system/tests/modules/router_test_directory/src/RouteTestSubscriber.php
index 3bc703b..72b824b 100644
--- a/core/modules/system/tests/modules/router_test_directory/src/RouteTestSubscriber.php
+++ b/core/modules/system/tests/modules/router_test_directory/src/RouteTestSubscriber.php
@@ -7,21 +7,82 @@
 
 namespace Drupal\router_test;
 
-use Drupal\Core\Routing\RouteSubscriberBase;
-use Symfony\Component\Routing\RouteCollection;
+use Drupal\Core\Routing\RouteBuildEvent;
+use Drupal\Core\Routing\RoutingEvents;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+use Symfony\Component\Routing\Route;
 
 /**
  * Listens to the dynamic route event and add a test route.
  */
-class RouteTestSubscriber extends RouteSubscriberBase {
+class RouteTestSubscriber implements EventSubscriberInterface {
 
   /**
    * {@inheritdoc}
    */
-  protected function alterRoutes(RouteCollection $collection) {
+  public static function getSubscribedEvents() {
+    $events[RoutingEvents::DYNAMIC] = 'onDynamicRoutes';
+    $events[RoutingEvents::ALTER] = 'onAlterRoutes';
+    return $events;
+  }
+
+  /**
+   * Adds dynamic routes for a specific collection from an event.
+   *
+   * @param \Drupal\Core\Routing\RouteBuildEvent $event
+   *   The route build event.
+   */
+  public function onDynamicRoutes(RouteBuildEvent $event) {
+    $collection = $event->getRouteCollection();
+    $route = new Route(
+      '/router_test/mixedCASE4',
+      [
+        '_controller' => '\Drupal\router_test\TestControllers::test2',
+      ],
+      [
+        '_access' => 'TRUE',
+      ]
+    );
+    $collection->add("router_test.mixedcase.4", $route);
+    $route = new Route(
+      '/router_test/tobealtered',
+      [
+        '_controller' => '\Drupal\router_test\TestControllers::test2',
+      ],
+      [
+        '_access' => 'TRUE',
+      ]
+    );
+    $collection->add("router_test.mixedcase.5", $route);
+  }
+
+  /**
+   * Alters existing routes for a specific collection from an event.
+   *
+   * @param \Drupal\Core\Routing\RouteBuildEvent $event
+   *   The route build event.
+   */
+  public function onAlterRoutes(RouteBuildEvent $event) {
+    $collection = $event->getRouteCollection();
     $route = $collection->get('router_test.6');
     // Change controller method from test1 to test5.
     $route->setDefault('_controller', '\Drupal\router_test\TestControllers::test5');
+    // Change a route path from lower case to mixed case.
+    $route = $collection->get('router_test.mixedcase.5');
+    $route->setPath('/router_tesT/MIXedcase5/ALTERED');
+    // We can also add routes in the alter, which happens in classes like
+    // \Drupal\content_translation\Routing\ContentTranslationRouteSubscriber
+    // that need to add routes based on other routes that are added dynamically.
+    $route = new Route(
+      '/router_test/mixedCASE6',
+      [
+        '_controller' => '\Drupal\router_test\TestControllers::test2',
+      ],
+      [
+        '_access' => 'TRUE',
+      ]
+    );
+    $collection->add("router_test.mixedcase.6", $route);
   }
 
 }
diff --git a/core/modules/views/src/Plugin/views/display/PathPluginBase.php b/core/modules/views/src/Plugin/views/display/PathPluginBase.php
index aab4f6d..f2a379b 100644
--- a/core/modules/views/src/Plugin/views/display/PathPluginBase.php
+++ b/core/modules/views/src/Plugin/views/display/PathPluginBase.php
@@ -243,7 +243,9 @@ public function alterRoutes(RouteCollection $collection) {
       // Ensure that we don't override a route which is already controlled by
       // views.
       if (!$route->hasDefault('view_id') && ('/' . $view_path == $route_path)) {
-        $parameters = $route->compile()->getPathVariables();
+        // The path variables array may have arbitrary keys, so take just the
+        // values to ensure we have a simple numeric array starting from 0.
+        $parameters = array_values($route->compile()->getPathVariables());
 
         // @todo Figure out whether we need to merge some settings (like
         // requirements).
diff --git a/core/modules/views/src/Tests/Wizard/BasicTest.php b/core/modules/views/src/Tests/Wizard/BasicTest.php
index 8a64df8..4216594 100644
--- a/core/modules/views/src/Tests/Wizard/BasicTest.php
+++ b/core/modules/views/src/Tests/Wizard/BasicTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Component\Serialization\Json;
 use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Url;
 use Drupal\views\Views;
 
@@ -66,9 +67,9 @@ function testViewsWizardAndListing() {
     $view2['description'] = $this->randomMachineName(16);
     $view2['page[create]'] = 1;
     $view2['page[title]'] = $this->randomMachineName(16);
-    $view2['page[path]'] = $this->randomMachineName(16);
+    $view2['page[path]'] = Unicode::strtolower($this->randomMachineName(16));
     $view2['page[feed]'] = 1;
-    $view2['page[feed_properties][path]'] = $this->randomMachineName(16);
+    $view2['page[feed_properties][path]'] = Unicode::strtolower($this->randomMachineName(16));
     $this->drupalPostForm('admin/structure/views/add', $view2, t('Save and edit'));
     $this->drupalGet($view2['page[path]']);
     $this->assertResponse(200);
@@ -115,7 +116,7 @@ function testViewsWizardAndListing() {
     $view3['show[type]'] = 'page';
     $view3['page[create]'] = 1;
     $view3['page[title]'] = $this->randomMachineName(16);
-    $view3['page[path]'] = $this->randomMachineName(16);
+    $view3['page[path]'] = Unicode::strtolower($this->randomMachineName(16));
     $view3['block[create]'] = 1;
     $view3['block[title]'] = $this->randomMachineName(16);
     $this->drupalPostForm('admin/structure/views/add', $view3, t('Save and edit'));
diff --git a/core/modules/views/src/Tests/Wizard/MenuTest.php b/core/modules/views/src/Tests/Wizard/MenuTest.php
index af6a98d..93c11c5 100644
--- a/core/modules/views/src/Tests/Wizard/MenuTest.php
+++ b/core/modules/views/src/Tests/Wizard/MenuTest.php
@@ -30,7 +30,7 @@ function testMenus() {
     $view['description'] = $this->randomMachineName(16);
     $view['page[create]'] = 1;
     $view['page[title]'] = $this->randomMachineName(16);
-    $view['page[path]'] = $this->randomMachineName(16);
+    $view['page[path]'] = strtolower($this->randomMachineName(16));
     $view['page[link]'] = 1;
     $view['page[link_properties][menu_name]'] = 'main';
     $view['page[link_properties][title]'] = $this->randomMachineName(16);