diff --git a/core/lib/Drupal/Core/Ajax/UpdateBuildIdCommand.php b/core/lib/Drupal/Core/Ajax/UpdateBuildIdCommand.php
index e034bdb..5eefc6f 100644
--- a/core/lib/Drupal/Core/Ajax/UpdateBuildIdCommand.php
+++ b/core/lib/Drupal/Core/Ajax/UpdateBuildIdCommand.php
@@ -14,7 +14,7 @@
  *
  * The primary use case for this Ajax command is to serve a new build ID to a
  * form served from the cache to an anonymous user, preventing one anonymous
- * user from accessing the form state of another anonymous users on Ajax enabled
+ * user from accessing the form state of another anonymous user on Ajax enabled
  * forms.
  *
  * This command is implemented by Drupal.AjaxCommands.prototype.update_build_id()
diff --git a/core/lib/Drupal/Core/Form/FormCache.php b/core/lib/Drupal/Core/Form/FormCache.php
index ddc05a0..4cc3f40 100644
--- a/core/lib/Drupal/Core/Form/FormCache.php
+++ b/core/lib/Drupal/Core/Form/FormCache.php
@@ -194,7 +194,7 @@ public function setCache($form_build_id, $form, FormStateInterface $form_state)
   }
 
   /**
-   * Wraps drupal_page_is_cacheable().
+   * Checks if the page is cacheable.
    */
   protected function isPageCacheable($allow_caching = NULL) {
     $request_policy = \Drupal::service('page_cache_request_policy');
diff --git a/core/modules/system/src/Tests/Form/StorageTest.php b/core/modules/system/src/Tests/Form/StorageTest.php
index 147cbc6..c8a4dc8 100644
--- a/core/modules/system/src/Tests/Form/StorageTest.php
+++ b/core/modules/system/src/Tests/Form/StorageTest.php
@@ -164,7 +164,7 @@ function testFormStatePersist() {
    * Verify that the form build-id remains the same when validation errors
    * occur on a mutable form.
    */
-  function testMutableForm() {
+  public function testMutableForm() {
     // Request the form with 'cache' query parameter to enable form caching.
     $this->drupalGet('form_test/form-storage', ['query' => ['cache' => 1]]);
     $buildIdFields = $this->xpath('//input[@name="form_build_id"]');
@@ -183,7 +183,7 @@ function testMutableForm() {
    * Verifies that form build-id is regenerated when loading an immutable form
    * from the cache.
    */
-  function testImmutableForm() {
+  public function testImmutableForm() {
     // Request the form with 'cache' query parameter to enable form caching.
     $this->drupalGet('form_test/form-storage', ['query' => ['cache' => 1, 'immutable' => 1]]);
     $buildIdFields = $this->xpath('//input[@name="form_build_id"]');
diff --git a/core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php b/core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php
index 302bb30..12a11cc 100644
--- a/core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php
+++ b/core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php
@@ -42,8 +42,8 @@ public function twoFormInstances() {
    *
    * Drupal 6 AHAH callbacks used to operate directly on forms retrieved using
    * form_get_cache and stored using form_set_cache after manipulation. This
-   * callback helps testing whether form_set_cache prevents resaving of immutable
-   * forms.
+   * callback helps testing whether form_set_cache prevents resaving of
+   * immutable forms.
    */
   public function storageLegacyHandler($form_build_id) {
     $form_state = new FormState();
diff --git a/core/modules/system/tests/modules/form_test/src/Form/FormTestStorageForm.php b/core/modules/system/tests/modules/form_test/src/Form/FormTestStorageForm.php
index dc44491..60e0cdb 100644
--- a/core/modules/system/tests/modules/form_test/src/Form/FormTestStorageForm.php
+++ b/core/modules/system/tests/modules/form_test/src/Form/FormTestStorageForm.php
@@ -88,7 +88,7 @@ public function buildForm(array $form, FormStateInterface $form_state) {
       $form_state->setCached();
     }
 
-    if (\Drupal::request()->get('immutable')) {
+    if ($this->getRequest()->get('immutable')) {
       $form_state->addBuildInfo('immutable', TRUE);
     }