diff --git a/core/modules/book/book.services.yml b/core/modules/book/book.services.yml
index 9ecb30d..762e60e 100644
--- a/core/modules/book/book.services.yml
+++ b/core/modules/book/book.services.yml
@@ -1,7 +1,7 @@
 services:
   book.breadcrumb:
     class: Drupal\book\BookBreadcrumbBuilder
-    arguments: ['@router.route_provider', '@plugin.manager.entity', '@access_manager', '@string_translation']
+    arguments: ['@router.route_provider', '@plugin.manager.entity', '@access_manager', '@string_translation', '@router.dynamic']
     tags:
       - { name: breadcrumb_builder, priority: 701 }
   book.manager:
diff --git a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkBreadcrumbBuilder.php b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkBreadcrumbBuilder.php
index ac94afc..996716e 100644
--- a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkBreadcrumbBuilder.php
+++ b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkBreadcrumbBuilder.php
@@ -13,6 +13,8 @@
 use Drupal\Core\Routing\RouteCompiler;
 use Drupal\Core\StringTranslation\TranslationInterface;
 use Drupal\Core\Access\AccessManager;
+use Symfony\Cmf\Component\Routing\DynamicRouter;
+use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\Routing\Exception\RouteNotFoundException;
 use Symfony\Component\Routing\Route;
@@ -53,11 +55,18 @@ class MenuLinkBreadcrumbBuilder implements BreadcrumbBuilderInterface {
   /**
    * The menu storage controller.
    *
-   * @var Drupal\Core\Config\Entity\ConfigStorageController
+   * @var \Drupal\Core\Config\Entity\ConfigStorageController
    */
   protected $menuStorage;
 
   /**
+   * The dynamic router service.
+   *
+   * @var \Symfony\Cmf\Component\Routing\DynamicRouter
+   */
+  protected $dynamicRouter;
+
+  /**
    * Constructs the MenuLinkBreadcrumbBuilder.
    *
    * @param \Drupal\Core\Routing\RouteProviderInterface $route_provider
@@ -68,13 +77,16 @@ class MenuLinkBreadcrumbBuilder implements BreadcrumbBuilderInterface {
    *   The menu link access service.
    * @param \Drupal\Core\StringTranslation\TranslationInterface $translation
    *   The translation manager service.
+   * @param \Symfony\Cmf\Component\Routing\DynamicRouter $dynamic_router
+   *   The dynamic router service.
    */
-  public function __construct(RouteProviderInterface $route_provider, EntityManager $entity_manager, AccessManager $access_manager, TranslationInterface $translation) {
+  public function __construct(RouteProviderInterface $route_provider, EntityManager $entity_manager, AccessManager $access_manager, TranslationInterface $translation, DynamicRouter $dynamic_router) {
     $this->routeProvider = $route_provider;
     $this->menuLinkStorage = $entity_manager->getStorageController('menu_link');
     $this->accessManager = $access_manager;
     $this->translation = $translation;
     $this->menuStorage = $entity_manager->getStorageController('menu');
+    $this->dynamicRouter = $dynamic_router;
   }
 
   /**
@@ -127,7 +139,7 @@ public function build(array $attributes) {
               if ($this->accessManager->checkNamedRoute($menu_link->route_name, $parameters)) {
                 // _menu_item_localize expects an upcasted map.
                 $map = $path_elements;
-                $this->upcastParameters($route, $attributes, $map);
+                $this->upcastParameters($route, $pattern, $map);
                 // @todo Move _menu_item_localize() to a service.
                 _menu_item_localize($menu_link, $map, FALSE);
                 // @todo Replace with link generator service when
@@ -169,12 +181,22 @@ public function build(array $attributes) {
    *
    * @param \Symfony\Component\Routing\Route $route
    *   The route object.
-   * @param array $attributes
-   *   The request attributes.
+   * @param string $href
+   *   The request path.
    * @param array $map
    *   The raw path map which is to be upcast.
    */
-  protected function upcastParameters(Route $route, array $attributes, array &$map) {
+  protected function upcastParameters(Route $route, $href, array &$map) {
+    $request = Request::create('/' . $href);
+    $request->attributes->set('_system_path', $href);
+    // Attempt to match this path to provide a fully built request.
+    try {
+      $request->attributes->add($this->dynamicRouter->matchRequest($request));
+    }
+    catch (NotFoundHttpException $e) {
+      return FALSE;
+    }
+
     // Populate the map with any matching values from the request.
     $path_bits = explode('/', trim($route->getPath(), '/'));
     foreach ($map as $index => $map_item) {
@@ -184,8 +206,8 @@ protected function upcastParameters(Route $route, array $attributes, array &$map
       if (isset($path_bits[$index]) && preg_match('/{(?<placeholder>.*)}/', $path_bits[$index], $matches)) {
         // If that placeholder is present on the request attributes, replace the
         // placeholder in the map with the value.
-        if (!empty($attributes[$matches['placeholder']])) {
-          $map[$index] = $attributes[$matches['placeholder']];
+        if ($request->attributes->has($matches['placeholder'])) {
+          $map[$index] = $request->attributes->get($matches['placeholder']);
         }
       }
     }
diff --git a/core/modules/menu_link/menu_link.services.yml b/core/modules/menu_link/menu_link.services.yml
index 272f249..7161f42 100644
--- a/core/modules/menu_link/menu_link.services.yml
+++ b/core/modules/menu_link/menu_link.services.yml
@@ -1,6 +1,6 @@
 services:
   menu_link.breadcrumb:
     class: Drupal\menu_link\MenuLinkBreadcrumbBuilder
-    arguments: ['@router.route_provider', '@plugin.manager.entity', '@access_manager', '@string_translation']
+    arguments: ['@router.route_provider', '@plugin.manager.entity', '@access_manager', '@string_translation', '@router.dynamic']
     tags:
       - { name: breadcrumb_builder, priority: 0 }