core/core.services.yml                             | 22 +++++++++++-----------
 .../Core/Cache/MenuActiveTrailCacheContext.php     |  2 +-
 .../Drupal/Core/Menu/MenuActiveTrailInterface.php  |  5 +++--
 core/modules/comment/comment.module                |  2 +-
 .../system/src/Plugin/Block/SystemMenuBlock.php    |  2 +-
 .../Tests/Cache/PageCacheTagsIntegrationTest.php   |  8 ++++----
 6 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/core/core.services.yml b/core/core.services.yml
index 1b60663..2eb4b93 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -21,6 +21,17 @@ services:
     arguments: ['@request_stack']
     tags:
       - { name: cache.context }
+  cache_context.url.pager:
+    class: Drupal\Core\Cache\PagerCacheContext
+    arguments: ['@request_stack']
+    tags:
+      - { name: cache.context}
+  cache_context.url.menu_active_trail:
+    class: Drupal\Core\Cache\MenuActiveTrailCacheContext
+    calls:
+      - [setContainer, ['@service_container']]
+    tags:
+      - { name: cache.context}
 
   cache_factory:
     class: Drupal\Core\Cache\CacheFactory
@@ -30,11 +41,6 @@ services:
   cache_contexts:
     class: Drupal\Core\Cache\CacheContexts
     arguments: ['@service_container', '%cache_contexts%' ]
-  cache_context.pager:
-    class: Drupal\Core\Cache\PagerCacheContext
-    arguments: ['@request_stack']
-    tags:
-      - { name: cache.context}
   cache_context.language:
     class: Drupal\Core\Cache\LanguageCacheContext
     arguments: ['@language_manager']
@@ -49,12 +55,6 @@ services:
     class: Drupal\Core\Cache\TimeZoneCacheContext
     tags:
       - { name: cache.context}
-  cache_context.menu.active_trail:
-    class: Drupal\Core\Cache\MenuActiveTrailCacheContext
-    calls:
-      - [setContainer, ['@service_container']]
-    tags:
-      - { name: cache.context}
   cache_tags.invalidator:
     parent: container.trait
     class: Drupal\Core\Cache\CacheTagsInvalidator
diff --git a/core/lib/Drupal/Core/Cache/MenuActiveTrailCacheContext.php b/core/lib/Drupal/Core/Cache/MenuActiveTrailCacheContext.php
index 7c41bee..7f0e226 100644
--- a/core/lib/Drupal/Core/Cache/MenuActiveTrailCacheContext.php
+++ b/core/lib/Drupal/Core/Cache/MenuActiveTrailCacheContext.php
@@ -27,7 +27,7 @@ public static function getLabel() {
   /**
    * {@inheritdoc}
    */
-  public function getContext($menu_name) {
+  public function getContext($menu_name = NULL) {
     $active_trail = $this->container->get('menu.active_trail')
       ->getActiveTrailIds($menu_name);
     return 'menu_trail.' . $menu_name . '|' . implode('|', $active_trail);
diff --git a/core/lib/Drupal/Core/Menu/MenuActiveTrailInterface.php b/core/lib/Drupal/Core/Menu/MenuActiveTrailInterface.php
index 49f4e99..be32e64 100644
--- a/core/lib/Drupal/Core/Menu/MenuActiveTrailInterface.php
+++ b/core/lib/Drupal/Core/Menu/MenuActiveTrailInterface.php
@@ -18,8 +18,9 @@
   /**
    * Gets the active trail IDs of the specified menu tree.
    *
-   * @param string $menu_name
-   *   The menu name of the requested tree.
+   * @param string|NULL $menu_name
+   *   (optional) The menu name of the requested tree. If omitted, all menu
+   *   trees will be searched.
    *
    * @return array
    *   An array containing the active trail: a list of plugin IDs.
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index 695018c..d4c2415 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -208,7 +208,7 @@ function comment_entity_build_defaults_alter(array &$build, EntityInterface $ent
     foreach ($entity->getFieldDefinitions() as $field_name => $definition) {
       if ($definition->getType() === 'comment' && ($display_options = $display->getComponent($field_name))) {
         $pager_id = $display_options['settings']['pager_id'];
-        $build['#cache']['contexts'][] = 'pager:' . $pager_id;
+        $build['#cache']['contexts'][] = 'url.pager:' . $pager_id;
       }
     }
   }
diff --git a/core/modules/system/src/Plugin/Block/SystemMenuBlock.php b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
index c07fba2..0d9ab37 100644
--- a/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
+++ b/core/modules/system/src/Plugin/Block/SystemMenuBlock.php
@@ -201,7 +201,7 @@ protected function getRequiredCacheContexts() {
     $menu_name = $this->getDerivativeId();
     return [
       'user.roles',
-      'menu.active_trail:' . $menu_name,
+      'url.menu_active_trail:' . $menu_name,
     ];
   }
 
diff --git a/core/modules/system/src/Tests/Cache/PageCacheTagsIntegrationTest.php b/core/modules/system/src/Tests/Cache/PageCacheTagsIntegrationTest.php
index b56a6ba..3fb4ea6 100644
--- a/core/modules/system/src/Tests/Cache/PageCacheTagsIntegrationTest.php
+++ b/core/modules/system/src/Tests/Cache/PageCacheTagsIntegrationTest.php
@@ -72,10 +72,10 @@ function testPageCacheTags() {
 
     $cache_contexts = [
       'language',
-      'menu.active_trail:account',
-      'menu.active_trail:footer',
-      'menu.active_trail:main',
-      'menu.active_trail:tools',
+      'url.menu_active_trail:account',
+      'url.menu_active_trail:footer',
+      'url.menu_active_trail:main',
+      'url.menu_active_trail:tools',
       'theme',
       'timezone',
       'user.roles',