diff --git a/core/lib/Drupal/Core/Entity/EntityFieldManager.php b/core/lib/Drupal/Core/Entity/EntityFieldManager.php
index 0357e99755..5919f9f243 100644
--- a/core/lib/Drupal/Core/Entity/EntityFieldManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityFieldManager.php
@@ -453,7 +453,16 @@ public function getFieldStorageDefinitions($entity_type_id) {
   }
 
   /**
-   * {@inheritdoc}
+   * Gets the active field storage definitions for a content entity type.
+   *
+   * @param string $entity_type_id
+   *   The entity type ID. Only content entities are supported.
+   *
+   * @return \Drupal\Core\Field\FieldStorageDefinitionInterface[]
+   *   An array of field storage definitions that are active in the current
+   *   request, keyed by field name.
+   *
+   * @internal
    */
   public function getActiveFieldStorageDefinitions($entity_type_id) {
     if (!isset($this->activeFieldStorageDefinitions[$entity_type_id])) {
diff --git a/core/lib/Drupal/Core/Entity/EntityFieldManagerInterface.php b/core/lib/Drupal/Core/Entity/EntityFieldManagerInterface.php
index 016fe15782..327d9e309f 100644
--- a/core/lib/Drupal/Core/Entity/EntityFieldManagerInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityFieldManagerInterface.php
@@ -61,18 +61,6 @@ public function getFieldDefinitions($entity_type_id, $bundle);
    */
   public function getFieldStorageDefinitions($entity_type_id);
 
-  /**
-   * Gets the active field storage definitions for a content entity type.
-   *
-   * @param string $entity_type_id
-   *   The entity type ID. Only content entities are supported.
-   *
-   * @return \Drupal\Core\Field\FieldStorageDefinitionInterface[]
-   *   An array of field storage definitions that are active in the current
-   *   request, keyed by field name.
-   */
-  public function getActiveFieldStorageDefinitions($entity_type_id);
-
   /**
    * Gets a lightweight map of fields across bundles.
    *
diff --git a/core/lib/Drupal/Core/Entity/EntityTypeManager.php b/core/lib/Drupal/Core/Entity/EntityTypeManager.php
index fe809af41e..5544e4a43d 100644
--- a/core/lib/Drupal/Core/Entity/EntityTypeManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityTypeManager.php
@@ -151,7 +151,15 @@ public function getDefinition($entity_type_id, $exception_on_invalid = TRUE) {
   }
 
   /**
-   * {@inheritdoc}
+   * Gets the active definition for a content entity type.
+   *
+   * @param string $entity_type_id
+   *   The entity type ID.
+   *
+   * @return \Drupal\Core\Entity\EntityTypeInterface
+   *   The active entity type definition.
+   *
+   * @internal
    */
   public function getActiveDefinition($entity_type_id) {
     if (!isset($this->activeDefinitions[$entity_type_id])) {
diff --git a/core/lib/Drupal/Core/Entity/EntityTypeManagerInterface.php b/core/lib/Drupal/Core/Entity/EntityTypeManagerInterface.php
index 5ef06443bf..4a5ec77745 100644
--- a/core/lib/Drupal/Core/Entity/EntityTypeManagerInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityTypeManagerInterface.php
@@ -148,15 +148,4 @@ public function getDefinition($entity_type_id, $exception_on_invalid = TRUE);
    */
   public function getDefinitions();
 
-  /**
-   * Gets the active definition for a content entity type.
-   *
-   * @param string $entity_type_id
-   *   The entity type ID.
-   *
-   * @return \Drupal\Core\Entity\EntityTypeInterface
-   *   The active entity type definition.
-   */
-  public function getActiveDefinition($entity_type_id);
-
 }
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
index 5e3fa64289..ff3c4cd7cd 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
@@ -153,8 +153,7 @@ public static function createInstance(ContainerInterface $container, EntityTypeI
       $container->get('language_manager'),
       $container->get('entity.memory_cache'),
       $container->get('entity_type.bundle.info'),
-      $container->get('entity_type.manager'),
-      $container->get('entity.last_installed_schema.repository')
+      $container->get('entity_type.manager')
     );
   }
 
diff --git a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
index f6eb340f9e..544327b539 100644
--- a/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
+++ b/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
@@ -118,7 +118,7 @@ class SqlContentEntityStorageSchema implements DynamicallyFieldableEntityStorage
    */
   public function __construct(EntityTypeManagerInterface $entity_type_manager, ContentEntityTypeInterface $entity_type, SqlContentEntityStorage $storage, Connection $database, EntityFieldManagerInterface $entity_field_manager = NULL) {
     $this->entityTypeManager = $entity_type_manager;
-    $this->storage = $storage;
+    $this->storage = clone $storage;
     $this->database = $database;
     if (!$entity_field_manager) {
       @trigger_error('Calling SqlContentEntityStorageSchema::__construct() with the $entity_field_manager argument is supported in drupal:8.7.0 and will be required before drupal:9.0.0. See https://www.drupal.org/node/2549139.', E_USER_DEPRECATED);
diff --git a/core/modules/jsonapi/tests/src/Functional/CommentTest.php b/core/modules/jsonapi/tests/src/Functional/CommentTest.php
index 0194177633..ddb7d0b8f8 100644
--- a/core/modules/jsonapi/tests/src/Functional/CommentTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/CommentTest.php
@@ -357,7 +357,7 @@ public function testPostIndividualSkipCommentApproval() {
     $response = $this->request('POST', $url, $request_options);
     $this->assertResourceResponse(201, FALSE, $response);
     $this->assertFalse(Json::decode((string) $response->getBody())['data']['attributes']['status']);
-    $this->assertFalse($this->entityStorage->loadUnchanged(2)->isPublished());
+    $this->assertFalse($this->getEntityStorage()->loadUnchanged(2)->isPublished());
 
     // Grant anonymous permission to skip comment approval.
     $this->grantPermissionsToTestedRole(['skip comment approval']);
@@ -366,7 +366,7 @@ public function testPostIndividualSkipCommentApproval() {
     $response = $this->request('POST', $url, $request_options);
     $this->assertResourceResponse(201, FALSE, $response);
     $this->assertTrue(Json::decode((string) $response->getBody())['data']['attributes']['status']);
-    $this->assertTrue($this->entityStorage->loadUnchanged(3)->isPublished());
+    $this->assertTrue($this->getEntityStorage()->loadUnchanged(3)->isPublished());
   }
 
   /**
diff --git a/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php b/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
index d2b638cb28..b5d37de2aa 100644
--- a/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
@@ -133,7 +133,7 @@ public function setUp() {
     $this->field->save();
 
     // Reload entity so that it has the new field.
-    $this->entity = $this->entityStorage->loadUnchanged($this->entity->id());
+    $this->entity = $this->getEntityStorage()->loadUnchanged($this->entity->id());
 
     $this->rebuildAll();
   }
diff --git a/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
index f50c15804a..d03f5f0ea0 100644
--- a/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
+++ b/core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
@@ -194,13 +194,6 @@
    */
   protected $account;
 
-  /**
-   * The entity storage.
-   *
-   * @var \Drupal\Core\Entity\EntityStorageInterface
-   */
-  protected $entityStorage;
-
   /**
    * The UUID key.
    *
@@ -247,7 +240,6 @@ public function setUp() {
 
     // Create an entity.
     $entity_type_manager = $this->container->get('entity_type.manager');
-    $this->entityStorage = $entity_type_manager->getStorage(static::$entityTypeId);
     $this->uuidKey = $entity_type_manager->getDefinition(static::$entityTypeId)
       ->getKey('uuid');
     $this->entity = $this->setUpFields($this->createEntity(), $this->account);
@@ -358,11 +350,11 @@ protected function setUpFields(EntityInterface $entity, UserInterface $account)
    * @throws \Drupal\Core\Entity\EntityStorageException
    */
   protected function getData() {
-    if ($this->entityStorage->getQuery()->count()->execute() < 2) {
+    if ($this->getEntityStorage()->getQuery()->count()->execute() < 2) {
       $this->createAnotherEntity('two');
     }
-    $query = $this->entityStorage->getQuery()->sort($this->entity->getEntityType()->getKey('id'));
-    return $this->entityStorage->loadMultiple($query->execute());
+    $query = $this->getEntityStorage()->getQuery()->sort($this->entity->getEntityType()->getKey('id'));
+    return $this->getEntityStorage()->loadMultiple($query->execute());
   }
 
   /**
@@ -408,7 +400,7 @@ protected function normalize(EntityInterface $entity, Url $url) {
   protected function createAnotherEntity($key) {
     $duplicate = $this->getEntityDuplicate($this->entity, $key);
     // Some entity types are not stored, hence they cannot be reloaded.
-    if (get_class($this->entityStorage) !== ContentEntityNullStorage::class) {
+    if (get_class($this->getEntityStorage()) !== ContentEntityNullStorage::class) {
       $duplicate->set('field_rest_test', 'Second collection entity');
     }
     $duplicate->save();
@@ -1980,7 +1972,7 @@ public function testPostIndividual() {
     $this->assertResourceResponse(201, FALSE, $response);
     $this->assertFalse($response->hasHeader('X-Drupal-Cache'));
     // If the entity is stored, perform extra checks.
-    if (get_class($this->entityStorage) !== ContentEntityNullStorage::class) {
+    if (get_class($this->getEntityStorage()) !== ContentEntityNullStorage::class) {
       $created_entity = $this->entityLoadUnchanged(static::$firstCreatedEntityId);
       $uuid = $created_entity->uuid();
       // @todo Remove line below in favor of commented line in https://www.drupal.org/project/jsonapi/issues/2878463.
@@ -1989,7 +1981,7 @@ public function testPostIndividual() {
         assert($created_entity instanceof RevisionableInterface);
         $location->setOption('query', ['resourceVersion' => 'id:' . $created_entity->getRevisionId()]);
       }
-      /* $location = $this->entityStorage->load(static::$firstCreatedEntityId)->toUrl('jsonapi')->setAbsolute(TRUE)->toString(); */
+      /* $location = $this->getEntityStorage()->load(static::$firstCreatedEntityId)->toUrl('jsonapi')->setAbsolute(TRUE)->toString(); */
       $this->assertSame([$location->setAbsolute()->toString()], $response->getHeader('Location'));
 
       // Assert that the entity was indeed created, and that the response body
@@ -2025,19 +2017,19 @@ public function testPostIndividual() {
     // 201 for well-formed request that creates another entity.
     // If the entity is stored, delete the first created entity (in case there
     // is a uniqueness constraint).
-    if (get_class($this->entityStorage) !== ContentEntityNullStorage::class) {
-      $this->entityStorage->load(static::$firstCreatedEntityId)->delete();
+    if (get_class($this->getEntityStorage()) !== ContentEntityNullStorage::class) {
+      $this->getEntityStorage()->load(static::$firstCreatedEntityId)->delete();
     }
     $response = $this->request('POST', $url, $request_options);
     $this->assertResourceResponse(201, FALSE, $response);
     $this->assertFalse($response->hasHeader('X-Drupal-Cache'));
 
     if ($this->entity->getEntityType()->getStorageClass() !== ContentEntityNullStorage::class && $this->entity->getEntityType()->hasKey('uuid')) {
-      $second_created_entity = $this->entityStorage->load(static::$secondCreatedEntityId);
+      $second_created_entity = $this->getEntityStorage()->load(static::$secondCreatedEntityId);
       $uuid = $second_created_entity->uuid();
       // @todo Remove line below in favor of commented line in https://www.drupal.org/project/jsonapi/issues/2878463.
       $location = Url::fromRoute(sprintf('jsonapi.%s.individual', static::$resourceTypeName), ['entity' => $uuid]);
-      /* $location = $this->entityStorage->load(static::$secondCreatedEntityId)->toUrl('jsonapi')->setAbsolute(TRUE)->toString(); */
+      /* $location = $this->getEntityStorage()->load(static::$secondCreatedEntityId)->toUrl('jsonapi')->setAbsolute(TRUE)->toString(); */
       if (static::$resourceTypeIsVersionable) {
         assert($created_entity instanceof RevisionableInterface);
         $location->setOption('query', ['resourceVersion' => 'id:' . $second_created_entity->getRevisionId()]);
@@ -2062,7 +2054,7 @@ public function testPostIndividual() {
 
       $response = $this->request('POST', $url, $request_options);
       $this->assertResourceResponse(201, FALSE, $response);
-      $entities = $this->entityStorage->loadByProperties([$this->uuidKey => $new_uuid]);
+      $entities = $this->getEntityStorage()->loadByProperties([$this->uuidKey => $new_uuid]);
       $new_entity = reset($entities);
       $this->assertNotNull($new_entity);
       $new_entity->delete();
@@ -2862,7 +2854,7 @@ public function testRevisions() {
 
     // Ensure the test entity has content_moderation fields attached to it.
     /* @var \Drupal\Core\Entity\FieldableEntityInterface|\Drupal\Core\Entity\TranslatableRevisionableInterface $entity */
-    $entity = $this->entityStorage->load($entity->id());
+    $entity = $this->getEntityStorage()->load($entity->id());
 
     // Set the published moderation state on the test entity.
     $entity->set('moderation_state', 'published');
@@ -3055,10 +3047,10 @@ public function testRevisions() {
     foreach ($test_relationship_urls as $revision_case) {
       list($revision_id, $relationship_url, $related_url) = $revision_case;
       // Load the revision that will be requested.
-      $this->entityStorage->resetCache([$entity->id()]);
+      $this->getEntityStorage()->resetCache([$entity->id()]);
       $revision = is_null($revision_id)
-        ? $this->entityStorage->load($entity->id())
-        : $this->entityStorage->loadRevision($revision_id);
+        ? $this->getEntityStorage()->load($entity->id())
+        : $this->getEntityStorage()->loadRevision($revision_id);
       // Request the relationship resource without access to the relationship
       // field.
       $actual_response = $this->request('GET', $relationship_url, $request_options);
@@ -3080,10 +3072,10 @@ public function testRevisions() {
     foreach ($test_relationship_urls as $revision_case) {
       list($revision_id, $relationship_url, $related_url) = $revision_case;
       // Load the revision that will be requested.
-      $this->entityStorage->resetCache([$entity->id()]);
+      $this->getEntityStorage()->resetCache([$entity->id()]);
       $revision = is_null($revision_id)
-        ? $this->entityStorage->load($entity->id())
-        : $this->entityStorage->loadRevision($revision_id);
+        ? $this->getEntityStorage()->load($entity->id())
+        : $this->getEntityStorage()->loadRevision($revision_id);
       // Request the relationship resource after granting access to the
       // relationship field.
       $actual_response = $this->request('GET', $relationship_url, $request_options);
@@ -3396,8 +3388,18 @@ protected function grantIncludedPermissions(array $include_paths = []) {
    * @todo Remove this after https://www.drupal.org/project/drupal/issues/3038706 lands.
    */
   protected function entityLoadUnchanged($id) {
-    $this->entityStorage->resetCache();
-    return $this->entityStorage->loadUnchanged($id);
+    $this->getEntityStorage()->resetCache();
+    return $this->getEntityStorage()->loadUnchanged($id);
+  }
+
+  /**
+   * Gets the entity storage for the entity type being tested.
+   *
+   * @return \Drupal\Core\Entity\EntityStorageInterface
+   *   An entity storage object.
+   */
+  protected function getEntityStorage() {
+    return \Drupal::entityTypeManager()->getStorage(static::$entityTypeId);
   }
 
 }
diff --git a/core/modules/jsonapi/tests/src/Functional/UserTest.php b/core/modules/jsonapi/tests/src/Functional/UserTest.php
index 1a72f7f2bf..7c431cd00c 100644
--- a/core/modules/jsonapi/tests/src/Functional/UserTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/UserTest.php
@@ -352,7 +352,7 @@ public function testPatchSecurityOtherUser() {
     $request_options[RequestOptions::BODY] = Json::encode($user1);
     $response = $this->request('PATCH', $url, $request_options);
     // Ensure the email address has not changed.
-    $this->assertEquals('admin@example.com', $this->entityStorage->loadUnchanged(1)->getEmail());
+    $this->assertEquals('admin@example.com', $this->getEntityStorage()->loadUnchanged(1)->getEmail());
     $this->assertResourceErrorResponse(403, 'The current user is not allowed to PATCH the selected field (uid). The entity ID cannot be changed.', $url, $response, '/data/attributes/uid');
   }