diff -u b/core/lib/Drupal/Core/Menu/LocalTaskManager.php b/core/lib/Drupal/Core/Menu/LocalTaskManager.php
--- b/core/lib/Drupal/Core/Menu/LocalTaskManager.php
+++ b/core/lib/Drupal/Core/Menu/LocalTaskManager.php
@@ -303,9 +303,7 @@
     // Pre-fetch all routes involved in the tree. This reduces the number
     // of SQL queries that would otherwise be triggered by the access manager.
     $routes = $route_names ? $this->routeProvider->getRoutesByNames($route_names) : array();
-
-    // @todo add cacheability data in https://www.drupal.org/node/2511516 so
-    // that we are not re-building inaccessible links on every page request.
+    
     foreach ($tree as $level => $instances) {
       /** @var $instances \Drupal\Core\Menu\LocalTaskInterface[] */
       foreach ($instances as $plugin_id => $child) {
@@ -330,7 +328,6 @@
           '#active' => $active,
           '#weight' => $child->getWeight(),
           '#access' => $this->accessManager->checkNamedRoute($route_name, $route_parameters, $this->account, TRUE),
-          '#cache' => ['contexts' => ['route']],
         ];
       }
     }
diff -u b/core/lib/Drupal/Core/Menu/Plugin/Block/LocalTasksBlock.php b/core/lib/Drupal/Core/Menu/Plugin/Block/LocalTasksBlock.php
--- b/core/lib/Drupal/Core/Menu/Plugin/Block/LocalTasksBlock.php
+++ b/core/lib/Drupal/Core/Menu/Plugin/Block/LocalTasksBlock.php
@@ -90,7 +90,7 @@
   public function build() {
     $config = $this->configuration;
     $cacheable_metadata = new CacheableMetadata();
-    $cacheable_metadata->addCacheContexts(['route.name']);
+    $cacheable_metadata->addCacheContexts(['route']);
     $tabs = [
       '#theme' => 'menu_local_tasks',
     ];
reverted:
--- b/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
+++ a/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
@@ -9,7 +9,6 @@
 
 use Drupal\Component\Plugin\Discovery\CachedDiscoveryInterface;
 use Drupal\Component\Plugin\Discovery\DiscoveryCachedTrait;
-use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Plugin\Discovery\ContainerDerivativeDiscoveryDecorator;
 use Drupal\Component\Plugin\PluginManagerBase;
 use Drupal\Component\Plugin\PluginManagerInterface;