.../Functional/EntityResource/EntityResourceTestBase.php   |  8 ++++----
 .../modules/rest/tests/src/Functional/ResourceTestBase.php | 14 ++++++++------
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php b/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
index 74a4b42..f9c4579 100644
--- a/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
@@ -393,7 +393,7 @@ public function testGet() {
 
 
     $this->config('rest.settings')->set('bc_entity_resource_permissions', TRUE)->save(TRUE);
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
 
 
     // DX: 403 when unauthorized.
@@ -614,7 +614,7 @@ public function testPost() {
 
 
     $this->config('rest.settings')->set('bc_entity_resource_permissions', TRUE)->save(TRUE);
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
     $request_options[RequestOptions::BODY] = $parseable_valid_request_body_2;
 
 
@@ -820,7 +820,7 @@ public function testPatch() {
 
 
     $this->config('rest.settings')->set('bc_entity_resource_permissions', TRUE)->save(TRUE);
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
     $request_options[RequestOptions::BODY] = $parseable_valid_request_body_2;
 
 
@@ -918,7 +918,7 @@ public function testDelete() {
 
 
     $this->config('rest.settings')->set('bc_entity_resource_permissions', TRUE)->save(TRUE);
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
     $this->entity = $this->createEntity();
     $url = $this->getUrl()->setOption('query', $url->getOption('query'));
 
diff --git a/core/modules/rest/tests/src/Functional/ResourceTestBase.php b/core/modules/rest/tests/src/Functional/ResourceTestBase.php
index 4f435c0..39537a9 100644
--- a/core/modules/rest/tests/src/Functional/ResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/ResourceTestBase.php
@@ -119,7 +119,7 @@ public function setUp() {
 
     // Ensure there's a clean slate: delete all REST resource config entities.
     $this->resourceConfigStorage->delete($this->resourceConfigStorage->loadMultiple());
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
   }
 
   /**
@@ -142,22 +142,24 @@ protected function provisionResource($resource_type, $formats = [], $authenticat
         'authentication' => $authentication,
       ]
     ])->save();
-    $this->refreshTestStateAfterRestResourceConfigChange();
+    $this->refreshTestStateAfterRestConfigChange();
   }
 
   /**
    * Refreshes the state of the tester to be in sync with the testee.
    *
-   * Should be called after every RestResourceConfig entity change.
+   * Should be called after every change made to:
+   * - RestResourceConfig entities
+   * - the 'rest.settings' simple configuration
    */
-  protected function refreshTestStateAfterRestResourceConfigChange() {
+  protected function refreshTestStateAfterRestConfigChange() {
     // Ensure that the cache tags invalidator has its internal values reset.
     // Otherwise the http_response cache tag invalidation won't work.
     $this->refreshVariables();
 
     // Tests using this base class may trigger route rebuilds due to changes to
-    // RestResourceConfig entities. Ensure we generate routes using an
-    // up-to-date router.
+    // RestResourceConfig entities or 'rest.settings'. Ensure the test generates
+    // routes using an up-to-date router.
     \Drupal::service('router.builder')->rebuildIfNeeded();
   }