diff --git a/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
index 3ac9914e09..5898d17ae6 100644
--- a/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
@@ -299,8 +299,8 @@ protected function setExpiresNoCache(Response $response) {
    */
   public static function getSubscribedEvents() {
     $events[KernelEvents::RESPONSE][] = array('onRespond');
-    // Execute before the onRespond method. We went with prio 16 as we want to
-    // run before static::onRespond().
+    // There is no specific reason for choosing 16 beside it should be executed
+    // before ::onRespond().
     $events[KernelEvents::RESPONSE][] = array('onAllResponds', 16);
     return $events;
   }
diff --git a/core/modules/rest/tests/src/Functional/EntityResource/Node/NodeResourceTestBase.php b/core/modules/rest/tests/src/Functional/EntityResource/Node/NodeResourceTestBase.php
index 08cb581962..d7651c4b90 100644
--- a/core/modules/rest/tests/src/Functional/EntityResource/Node/NodeResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/EntityResource/Node/NodeResourceTestBase.php
@@ -4,7 +4,6 @@
 
 use Drupal\node\Entity\Node;
 use Drupal\node\Entity\NodeType;
-use Drupal\rest\Entity\RestResourceConfig;
 use Drupal\Tests\rest\Functional\EntityResource\EntityResourceTestBase;
 use Drupal\user\Entity\User;
 
diff --git a/core/modules/rest/tests/src/Functional/ResourceTestBase.php b/core/modules/rest/tests/src/Functional/ResourceTestBase.php
index 4cde407744..db42927b79 100644
--- a/core/modules/rest/tests/src/Functional/ResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/ResourceTestBase.php
@@ -131,7 +131,7 @@ public function setUp() {
     // Ensure there's a clean slate: delete all REST resource config entities.
     $this->resourceConfigStorage->delete($this->resourceConfigStorage->loadMultiple());
     // If we remove resources we also need to ensure they don't stick in the
-    // router.
+    // {router} table.
     \Drupal::service('router.builder')->rebuild();
   }
 
@@ -155,6 +155,9 @@ protected function provisionResource($resource_type, $formats = [], $authenticat
         'authentication' => $authentication,
       ]
     ])->save();
+    // Ensure that the cache tags invalidator has its internal values reset.
+    // Otherwise the http_response cache tag invalidation won't work.
+    $this->refreshVariables();
     \Drupal::service('router.builder')->rebuild();
   }