diff --git a/core/core.services.yml b/core/core.services.yml
index ee319c3..6094635 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -855,6 +855,10 @@ services:
     arguments: ['@class_resolver', '@current_route_match', '%main_content_renderers%']
     tags:
       - { name: event_subscriber }
+  accept_negotiation_406:
+    class: Drupal\Core\EventSubscriber\AcceptNegotiation406
+    tags:
+      - { name: event_subscriber, priority: -10 }
   main_content_renderer.html:
     class: Drupal\Core\Render\MainContent\HtmlRenderer
     arguments: ['@title_resolver', '@plugin.manager.display_variant', '@event_dispatcher', '@element_info', '@module_handler', '@renderer', '@render_cache', '@cache_contexts_manager']
diff --git a/core/lib/Drupal/Core/EventSubscriber/ExceptionJsonSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/ExceptionJsonSubscriber.php
index 9610e8d..70e4208 100644
--- a/core/lib/Drupal/Core/EventSubscriber/ExceptionJsonSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/ExceptionJsonSubscriber.php
@@ -65,4 +65,15 @@ public function on405(GetResponseForExceptionEvent $event) {
     $event->setResponse($response);
   }
 
+  /**
+   * Handles a 406 error for JSON.
+   *
+   * @param \Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent $event
+   *   The event to process.
+   */
+  public function on406(GetResponseForExceptionEvent $event) {
+    $response = new JsonResponse(array('message' => $event->getException()->getMessage()), Response::HTTP_NOT_ACCEPTABLE);
+    $event->setResponse($response);
+  }
+
 }