diff --git a/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalMultilingualTest.php b/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalMultilingualTest.php
index 16799ef6f44bbc5c2258c685cbe5758f307a520e..01e01db7dcea870882445f5f8f8e484de2657ec6 100644
--- a/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalMultilingualTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalMultilingualTest.php
@@ -15,7 +15,6 @@
  * Tests JSON:API multilingual support.
  *
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalTest.php b/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalTest.php
index bea8773efbcfe5d0e9ab43121451327440484c35..a9fceada928eca33cf8274bf2e33c81ce6e008ec 100644
--- a/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalTest.php
@@ -11,7 +11,6 @@
  * General functional test class.
  *
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
@@ -271,7 +270,7 @@ public function testRead() {
     ]);
     $response = $this->request('GET', $user_url, [
       'auth' => [
-        $this->userCanViewProfiles->getUsername(),
+        $this->userCanViewProfiles->getAccountName(),
         $this->userCanViewProfiles->pass_raw,
       ],
     ]);
@@ -564,7 +563,7 @@ public function testWrite() {
     ];
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $created_response = Json::decode($response->getBody()->__toString());
@@ -587,7 +586,7 @@ public function testWrite() {
     // 2.1 Authorization error with a user without create permissions.
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->userCanViewProfiles->getUsername(), $this->userCanViewProfiles->pass_raw],
+      'auth' => [$this->userCanViewProfiles->getAccountName(), $this->userCanViewProfiles->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $created_response = Json::decode($response->getBody()->__toString());
@@ -598,7 +597,7 @@ public function testWrite() {
     // 3. Missing Content-Type error.
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Accept' => 'application/vnd.api+json'],
     ]);
     $created_response = Json::decode($response->getBody()->__toString());
@@ -609,7 +608,7 @@ public function testWrite() {
     $invalid_body['data']['id'] = Node::load(1)->uuid();
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($invalid_body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Accept' => 'application/vnd.api+json',
         'Content-Type' => 'application/vnd.api+json',
@@ -625,7 +624,7 @@ public function testWrite() {
     $body_invalid_tags['data']['relationships']['field_tags']['data'][1]['id'] = 'ipsum';
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($body_invalid_tags),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $created_response = Json::decode($response->getBody()->__toString());
@@ -633,7 +632,7 @@ public function testWrite() {
     // 6. Decoding error.
     $response = $this->request('POST', $collection_url, [
       'body' => '{"bad json",,,}',
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
@@ -646,7 +645,7 @@ public function testWrite() {
     // 6.1 Denormalizing error.
     $response = $this->request('POST', $collection_url, [
       'body' => '{"data":{"type":"something"},"valid yet nonsensical json":[]}',
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
@@ -662,7 +661,7 @@ public function testWrite() {
     $malformed_body['relationships'] = $body['data']['relationships'];
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($malformed_body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Accept' => 'application/vnd.api+json',
         'Content-Type' => 'application/vnd.api+json',
@@ -678,7 +677,7 @@ public function testWrite() {
     unset($missing_type['data']['type']);
     $response = $this->request('POST', $collection_url, [
       'body' => Json::encode($missing_type),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Accept' => 'application/vnd.api+json',
         'Content-Type' => 'application/vnd.api+json',
@@ -702,7 +701,7 @@ public function testWrite() {
     ]);
     $response = $this->request('PATCH', $individual_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $updated_response = Json::decode($response->getBody()->__toString());
@@ -722,7 +721,7 @@ public function testWrite() {
     ]);
     $response = $this->request('PATCH', $individual_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->userCanViewProfiles->getUsername(), $this->userCanViewProfiles->pass_raw],
+      'auth' => [$this->userCanViewProfiles->getAccountName(), $this->userCanViewProfiles->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $this->assertEquals(403, $response->getStatusCode());
@@ -740,7 +739,7 @@ public function testWrite() {
     ];
     $response = $this->request('PATCH', $individual_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $updated_response = Json::decode($response->getBody()->__toString());
@@ -764,7 +763,7 @@ public function testWrite() {
     ]);
     $response = $this->request('POST', $relationship_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $updated_response = Json::decode($response->getBody()->__toString());
@@ -783,7 +782,7 @@ public function testWrite() {
     ];
     $response = $this->request('PATCH', $relationship_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $this->assertEquals(204, $response->getStatusCode());
@@ -791,7 +790,7 @@ public function testWrite() {
     // 11. Successful DELETE to related endpoint.
     $response = $this->request('DELETE', $relationship_url, [
       // Send a request with no body.
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
@@ -812,7 +811,7 @@ public function testWrite() {
     $response = $this->request('DELETE', $relationship_url, [
       // Remove the existing relationship item.
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => ['Content-Type' => 'application/vnd.api+json'],
     ]);
     $this->assertEquals(204, $response->getStatusCode());
@@ -834,7 +833,7 @@ public function testWrite() {
     ];
     $response = $this->request('PATCH', $individual_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
@@ -863,7 +862,7 @@ public function testWrite() {
     ];
     $response = $this->request('PATCH', $individual_url, [
       'body' => Json::encode($body),
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
       'headers' => [
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
@@ -875,7 +874,7 @@ public function testWrite() {
       $updated_response['errors']['0']['detail']);
     // 14. Successful DELETE.
     $response = $this->request('DELETE', $individual_url, [
-      'auth' => [$this->user->getUsername(), $this->user->pass_raw],
+      'auth' => [$this->user->getAccountName(), $this->user->pass_raw],
     ]);
     $this->assertEquals(204, $response->getStatusCode());
     $response = $this->request('GET', $individual_url, []);
diff --git a/core/modules/jsonapi/tests/src/Functional/JsonApiRegressionTest.php b/core/modules/jsonapi/tests/src/Functional/JsonApiRegressionTest.php
index fde4ab22b6cbff5ab27b33332f80833081d5d160..bd05177b8c9532f3d23de2fb4ac991758a32c6c8 100644
--- a/core/modules/jsonapi/tests/src/Functional/JsonApiRegressionTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/JsonApiRegressionTest.php
@@ -26,7 +26,6 @@
  * JSON:API regression tests.
  *
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
@@ -70,7 +69,7 @@ public function testBundleSpecificTargetEntityTypeFromIssue2953207() {
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/comment/tcomment?include=entity_id&filter[entity_id.name]=foobar'), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -134,7 +133,7 @@ public function testDeepNestedIncludeMultiTargetEntityTypeFieldFromIssue2973681(
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/node/page?include=field_comment,field_comment.entity_id,field_comment.entity_id.uid'), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -181,7 +180,7 @@ public function testBundlelessRelationshipMutationFromIssue2973681() {
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
       ],
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
       RequestOptions::JSON => [
         'data' => [
           ['type' => 'user--user', 'id' => $target->uuid()],
@@ -221,7 +220,7 @@ public function testGetTermWhenMultipleVocabulariesExistFromIssue2977879() {
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/taxonomy_term/one'), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -283,7 +282,7 @@ public function testDanglingReferencesInAnEntityReferenceFieldFromIssue2968972()
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
       ],
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
       RequestOptions::JSON => [
         'data' => [
           'type' => 'node--journal_article',
@@ -322,7 +321,7 @@ public function testGetNodeCollectionWithHookNodeGrantsImplementationsFromIssue2
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/node/article'), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -408,7 +407,7 @@ public function testDanglingReferencesInAnEntityReferenceFieldFromIssue2984647()
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
       ],
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
     ];
     $issue_node->delete();
     $response = $this->request('GET', $url, $request_options);
@@ -469,7 +468,7 @@ public function testThatRoutesAreRebuiltAfterDataModelChangesFromIssue2984886()
     $user = $this->drupalCreateUser(['access content']);
     $request_options = [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ];
@@ -563,7 +562,7 @@ public function testDenormalizeAliasedRelationshipFromIssue2953207() {
     // Test.
     $response = $this->request('PATCH', Url::fromUri(sprintf('internal:/jsonapi/taxonomy_term/tags/%s/relationships/%s', Term::load(1)->uuid(), $public_relationship_field_name)), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
       RequestOptions::HEADERS => [
@@ -637,7 +636,7 @@ public function testFilterByIdFromIssue3015759() {
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/shortcut/default?filter[drupal_internal__id]=' . $shortcut->id()), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -689,7 +688,7 @@ public function testPatchingDateTimeNormalizedWrongTimeZoneIssue3021194() {
     ]);
     $response = $this->request('GET', Url::fromUri('internal:/jsonapi/node/page/' . $page->uuid()), [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ]);
@@ -757,7 +756,7 @@ public function testPatchingDateTimeFieldsFromIssue3021194() {
     ]);
     $request_options = [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
       RequestOptions::HEADERS => [
@@ -801,7 +800,7 @@ public function testPostToIncludeUrlDoesNotReturnIncludeFromIssue3026030() {
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
       ],
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
       RequestOptions::JSON => [
         'data' => [
           'type' => 'node--page',
@@ -846,7 +845,7 @@ public function testPatchToIncludeUrlDoesNotReturnIncludeFromIssue3026030() {
         'Content-Type' => 'application/vnd.api+json',
         'Accept' => 'application/vnd.api+json',
       ],
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
       RequestOptions::JSON => [
         'data' => [
           'type' => 'node--page',
@@ -887,7 +886,7 @@ public function testMapFieldTypeNormalizationFromIssue3040590() {
     // Test.
     $url = Url::fromUri(sprintf('internal:/jsonapi/entity_test_map_field/entity_test_map_field', $entity->uuid()));
     $request_options = [
-      RequestOptions::AUTH => [$user->getUsername(), $user->pass_raw],
+      RequestOptions::AUTH => [$user->getAccountName(), $user->pass_raw],
     ];
     $response = $this->request('GET', $url, $request_options);
     $this->assertSame(200, $response->getStatusCode());
@@ -931,7 +930,7 @@ public function testRecursionDetectedWhenResponseContainsViolationsFrom3042124()
     $admin = $this->drupalCreateUser([], 'Gandalf', TRUE);
 
     // Make request as regular user.
-    $request_options[RequestOptions::AUTH] = [$user->getUsername(), $user->pass_raw];
+    $request_options[RequestOptions::AUTH] = [$user->getAccountName(), $user->pass_raw];
     $this->request('POST', $url, $request_options);
     $response = $this->request('POST', $url, $request_options);
 
@@ -942,7 +941,7 @@ public function testRecursionDetectedWhenResponseContainsViolationsFrom3042124()
     $this->assertSame(sprintf('title: This value should not be null.'), $data['errors'][0]['detail']);
 
     // Make request as regular user.
-    $request_options[RequestOptions::AUTH] = [$admin->getUsername(), $admin->pass_raw];
+    $request_options[RequestOptions::AUTH] = [$admin->getAccountName(), $admin->pass_raw];
     $this->request('POST', $url, $request_options);
     $response = $this->request('POST', $url, $request_options);
 
@@ -981,7 +980,7 @@ public function testLeakedCacheMetadataViaRdfFromIssue3053827() {
     $user = $this->drupalCreateUser(['access comments']);
     $request_options = [
       RequestOptions::AUTH => [
-        $user->getUsername(),
+        $user->getAccountName(),
         $user->pass_raw,
       ],
     ];
diff --git a/core/modules/jsonapi/tests/src/Functional/RestExportJsonApiUnsupported.php b/core/modules/jsonapi/tests/src/Functional/RestExportJsonApiUnsupported.php
index 5e8387711912fa54fa917431f1e278836528e8a1..7efe1aa2e189f4cd32ea1330f0a9e6e69c328e84 100644
--- a/core/modules/jsonapi/tests/src/Functional/RestExportJsonApiUnsupported.php
+++ b/core/modules/jsonapi/tests/src/Functional/RestExportJsonApiUnsupported.php
@@ -9,7 +9,6 @@
  * Ensures that the 'api_json' format is not supported by the REST module.
  *
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Functional/RestJsonApiUnsupported.php b/core/modules/jsonapi/tests/src/Functional/RestJsonApiUnsupported.php
index 87c0f61b2c7edf565d157ecb54938cb317b901b9..8577caca29f4a62fdc4d4bcbba5cd02f3a7311f3 100644
--- a/core/modules/jsonapi/tests/src/Functional/RestJsonApiUnsupported.php
+++ b/core/modules/jsonapi/tests/src/Functional/RestJsonApiUnsupported.php
@@ -12,7 +12,6 @@
  * Ensures that the 'api_json' format is not supported by the REST module.
  *
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Kernel/Context/FieldResolverTest.php b/core/modules/jsonapi/tests/src/Kernel/Context/FieldResolverTest.php
index df693f93efd7458f004020982a50d8fbaecc8d42..e3c569a96389352615b7ab3f3091ca11f2e5e589 100644
--- a/core/modules/jsonapi/tests/src/Kernel/Context/FieldResolverTest.php
+++ b/core/modules/jsonapi/tests/src/Kernel/Context/FieldResolverTest.php
@@ -11,7 +11,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Context\FieldResolver
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Kernel/Controller/EntityResourceTest.php b/core/modules/jsonapi/tests/src/Kernel/Controller/EntityResourceTest.php
index 7270b63af2f361d96f265a9d2c5c72a05bb26ad2..3bbe465aad92aa87b4ec0b95e686947c2ccb7db9 100644
--- a/core/modules/jsonapi/tests/src/Kernel/Controller/EntityResourceTest.php
+++ b/core/modules/jsonapi/tests/src/Kernel/Controller/EntityResourceTest.php
@@ -10,7 +10,6 @@
 use Drupal\jsonapi\JsonApiResource\ResourceIdentifier;
 use Drupal\jsonapi\JsonApiResource\ResourceObject;
 use Drupal\jsonapi\ResourceType\ResourceType;
-use Drupal\jsonapi\Controller\EntityResource;
 use Drupal\jsonapi\JsonApiResource\Data;
 use Drupal\jsonapi\JsonApiResource\JsonApiDocumentTopLevel;
 use Drupal\node\Entity\Node;
@@ -27,7 +26,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Controller\EntityResource
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
@@ -187,19 +185,7 @@ protected function setUp() {
    *   An EntityResource instance.
    */
   protected function createEntityResource() {
-    return new EntityResource(
-      $this->container->get('entity_type.manager'),
-      $this->container->get('entity_field.manager'),
-      $this->container->get('jsonapi.resource_type.repository'),
-      $this->container->get('renderer'),
-      $this->container->get('entity.repository'),
-      $this->container->get('jsonapi.include_resolver'),
-      $this->container->get('jsonapi.entity_access_checker'),
-      $this->container->get('jsonapi.field_resolver'),
-      $this->container->get('jsonapi.serializer'),
-      $this->container->get('datetime.time'),
-      $this->container->get('current_user')
-    );
+    return $this->container->get('jsonapi.entity_resource');
   }
 
   /**
@@ -422,7 +408,8 @@ public function testCreateIndividual() {
     $response = $this->entityResource->createIndividual($resource_type, $request);
     // As a side effect, the node will also be saved.
     $this->assertInstanceOf(JsonApiDocumentTopLevel::class, $response->getResponseData());
-    $this->assertTrue(entity_load_multiple_by_properties('node', ['uuid' => $response->getResponseData()->getData()->getIterator()->offsetGet(0)->getId()]));
+    $entity_type_manager = $this->container->get('entity_type.manager');
+    $this->assertTrue($entity_type_manager->getStorage('node')->loadByProperties(['uuid' => $response->getResponseData()->getData()->getIterator()->offsetGet(0)->getId()]));
     $this->assertEquals(201, $response->getStatusCode());
   }
 
diff --git a/core/modules/jsonapi/tests/src/Kernel/Normalizer/JsonApiDocumentTopLevelNormalizerTest.php b/core/modules/jsonapi/tests/src/Kernel/Normalizer/JsonApiDocumentTopLevelNormalizerTest.php
index b1398d0cd9e23f7f0bc97280cd5f3c656621e753..b4ba1b3b1dc793fa0b2cb6816113258b85a44765 100644
--- a/core/modules/jsonapi/tests/src/Kernel/Normalizer/JsonApiDocumentTopLevelNormalizerTest.php
+++ b/core/modules/jsonapi/tests/src/Kernel/Normalizer/JsonApiDocumentTopLevelNormalizerTest.php
@@ -31,7 +31,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Normalizer\JsonApiDocumentTopLevelNormalizer
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Kernel/Query/FilterTest.php b/core/modules/jsonapi/tests/src/Kernel/Query/FilterTest.php
index 3c1e3820b1bfafd7dec9df33362c2729dd900f65..2a149acc23c68180e35a8fbc577911f140f2c4e2 100644
--- a/core/modules/jsonapi/tests/src/Kernel/Query/FilterTest.php
+++ b/core/modules/jsonapi/tests/src/Kernel/Query/FilterTest.php
@@ -17,7 +17,6 @@
  * @coversDefaultClass \Drupal\jsonapi\Query\Filter
  * @group jsonapi
  * @group jsonapi_query
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Kernel/ResourceType/ResourceTypeRepositoryTest.php b/core/modules/jsonapi/tests/src/Kernel/ResourceType/ResourceTypeRepositoryTest.php
index 34da1445a7ce74d2be698bb856fe70565f442219..2355b1dc1677b42a660ed76aacd51bfc5a28a07f 100644
--- a/core/modules/jsonapi/tests/src/Kernel/ResourceType/ResourceTypeRepositoryTest.php
+++ b/core/modules/jsonapi/tests/src/Kernel/ResourceType/ResourceTypeRepositoryTest.php
@@ -9,7 +9,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\ResourceType\ResourceTypeRepository
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionGroupTest.php b/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionGroupTest.php
index 67c4d8c207baf663ae5989b4409c1f2506ce3219..e7813de97a2feb2bc567ad70b356151399ebef73 100644
--- a/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionGroupTest.php
+++ b/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionGroupTest.php
@@ -8,7 +8,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Query\EntityConditionGroup
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionTest.php b/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionTest.php
index c8b8b02beacf1e7280b841cfddf452462c2b4667..4b07ced975b53678c6edd550a1627168c2aa2ac8 100644
--- a/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionTest.php
+++ b/core/modules/jsonapi/tests/src/Unit/Query/EntityConditionTest.php
@@ -12,7 +12,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Query\EntityCondition
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Unit/Query/OffsetPageTest.php b/core/modules/jsonapi/tests/src/Unit/Query/OffsetPageTest.php
index 5e9287e7fec89df6e86dc9e392295daff1df9e77..b1272c0ff9710d26b98a9295b2dd69f92edc9cc9 100644
--- a/core/modules/jsonapi/tests/src/Unit/Query/OffsetPageTest.php
+++ b/core/modules/jsonapi/tests/src/Unit/Query/OffsetPageTest.php
@@ -12,7 +12,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Query\OffsetPage
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */
diff --git a/core/modules/jsonapi/tests/src/Unit/Query/SortTest.php b/core/modules/jsonapi/tests/src/Unit/Query/SortTest.php
index c97a562c11ee413c42395f6e7b87a800ce133413..fdf1dbbaf2d0de2e0703e57a9f3484ea615dae9e 100644
--- a/core/modules/jsonapi/tests/src/Unit/Query/SortTest.php
+++ b/core/modules/jsonapi/tests/src/Unit/Query/SortTest.php
@@ -12,7 +12,6 @@
 /**
  * @coversDefaultClass \Drupal\jsonapi\Query\Sort
  * @group jsonapi
- * @group legacy
  *
  * @internal
  */