diff -u b/core/lib/Drupal/Core/Entity/EntityDisplayBase.php b/core/lib/Drupal/Core/Entity/EntityDisplayBase.php
--- b/core/lib/Drupal/Core/Entity/EntityDisplayBase.php
+++ b/core/lib/Drupal/Core/Entity/EntityDisplayBase.php
@@ -602,19 +602,18 @@
    * @param string $name
    *   The name of the element.
    *
-   * @return \Drupal\Core\Entity\DisplayComponentHandlerInterface|false
+   * @return \Drupal\Core\Entity\DisplayComponentHandlerInterface
    *   The display component handler.
    */
   public function getComponentHandlerByElementName($name) {
     if (!isset($this->handlers[$name])) {
       $handlers = $this->handlerManager->getDefinitions();
-      $handler = FALSE;
       foreach (array_keys($handlers) as $type) {
         $handler = $this->getComponentHandler($type);
         if ($handler && $handler->hasElement($name)) {
           break;
         }
-        $handler = FALSE;
+        $handler = NULL;
       }
       $this->handlers[$name] = $handler;
     }
diff -u b/core/lib/Drupal/Core/Field/FormatterPluginManager.php b/core/lib/Drupal/Core/Field/FormatterPluginManager.php
--- b/core/lib/Drupal/Core/Field/FormatterPluginManager.php
+++ b/core/lib/Drupal/Core/Field/FormatterPluginManager.php
@@ -128,6 +128,7 @@
     $configuration += [
       'field_definition' => $field_definition,
       'view_mode' => $options['view_mode'],
+      'label' => $field_definition->getLabel(),
     ];
     return $this->createInstance($plugin_id, $configuration);
   }
only in patch2:
unchanged:
--- /dev/null
+++ b/core/modules/field/tests/src/Unit/Plugin/DisplayComponent/FieldDisplayComponentHandlerTest.php
@@ -0,0 +1,464 @@
+<?php
+
+namespace Drupal\Tests\field\Unit;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\Entity\EntityFieldManagerInterface;
+use Drupal\Core\Entity\Plugin\DisplayComponent\FieldDisplayComponentHandler;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\Field\FieldTypePluginManager;
+use Drupal\Core\Field\FormatterPluginManager;
+use Drupal\Core\Field\Plugin\Field\FieldWidget\StringTextfieldWidget;
+use Drupal\Core\Field\WidgetPluginManager;
+use Drupal\Core\TypedData\TypedDataManagerInterface;
+use Drupal\Tests\UnitTestCase;
+use Drupal\text\Plugin\Field\FieldFormatter\TextDefaultFormatter;
+
+/**
+ * Tests display component handler.
+ *
+ * @group field
+ */
+class FieldDisplayComponentHandlerTest extends UnitTestCase {
+
+  /**
+   * The field definition used in this test.
+   *
+   * @var \Drupal\Core\Field\BaseFieldDefinition
+   */
+  protected $definition;
+
+  /**
+   * The default display.
+   *
+   * @var \Drupal\Core\Entity\Display\EntityViewDisplayInterface
+   */
+  protected $fieldDefinitions;
+
+  /**
+   * The entity field manager.
+   *
+   * @var \Drupal\Core\Field\FieldTypePluginManager|\PHPUnit\Framework\MockObject\MockObject
+   */
+  protected $entityFieldManager;
+
+  /**
+   * The formatter plugin manager.
+   *
+   * @var \Drupal\Core\Field\FormatterPluginManager|\PHPUnit\Framework\MockObject\MockObject
+   */
+  protected $formatterPluginManager;
+
+  /**
+   * The widget plugin manager.
+   *
+   * @var \Drupal\Core\Field\WidgetPluginManager|\PHPUnit\Framework\MockObject\MockObject
+   */
+  protected $widgetPluginManager;
+
+  /**
+   * The default component handler.
+   *
+   * @var \Drupal\Core\Entity\Plugin\DisplayComponent\FieldDisplayComponentHandler
+   */
+  protected $handler;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+    $module_name = 'field';
+    $module_dir = dirname(__DIR__, 4);
+    $namespaces = new \ArrayObject();
+    $namespaces["Drupal\\$module_name"] = $module_dir . '/src';
+
+    $module_handler = $this->createMock('Drupal\Core\Extension\ModuleHandlerInterface');
+    $typed_data_manager = $this->createMock(TypedDataManagerInterface::class);
+    $plugin_manager = new FieldTypePluginManager(
+      $namespaces,
+      $this->createMock('Drupal\Core\Cache\CacheBackendInterface'),
+      $module_handler,
+      $typed_data_manager
+    );
+
+    $container = new ContainerBuilder();
+    $container->set('plugin.manager.field.field_type', $plugin_manager);
+    \Drupal::setContainer($container);
+
+    $this->formatterPluginManager = $this->getMockBuilder(FormatterPluginManager::class)
+      ->disableOriginalConstructor()
+      ->getMock();
+    $this->widgetPluginManager = $this->getMockBuilder(WidgetPluginManager::class)
+      ->disableOriginalConstructor()
+      ->getMock();
+    $this->entityFieldManager = $this->getMockBuilder(EntityFieldManagerInterface::class)
+      ->onlyMethods(['getFieldDefinitions'])
+      ->getMockForAbstractClass();
+
+    // Create test definitions.
+    $this->definition = BaseFieldDefinition::create('text');
+    $this->definitions = $this->getTestFieldDefinitions();
+    $this->entityFieldManager->expects($this->any())
+      ->method('getFieldDefinitions')
+      ->willReturn($this->definitions);
+
+    // Create a field display component handler to test.
+    $this->handler = new FieldDisplayComponentHandler([], 'test', [], $this->formatterPluginManager, $this->widgetPluginManager, $this->entityFieldManager);
+  }
+
+  /**
+   * Tests MassageIn.
+   *
+   * @covers ::massageIn()
+   *
+   * @dataProvider providerTestMassageIn
+   */
+  public function testMassageIn($field_name, $display_context, $expected) {
+    $this->formatterPluginManager->expects($this->any())
+      ->method('prepareConfiguration')
+      ->willReturn('formatter configuration');
+    $this->widgetPluginManager->expects($this->any())
+      ->method('prepareConfiguration')
+      ->willReturn('widget configuration');
+
+    $this->handler->setContext([
+      'entity_type' => 'anything',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'massageIn');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, [$field_name, []]);
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testGetDisplayableField().
+   */
+  public function providerTestMassageIn() {
+    return [
+      'no field definition' => [
+        'not_exist',
+        '',
+        [],
+      ],
+      'widget' => [
+        'title',
+        'form',
+        'widget configuration',
+      ],
+      'formatter' => [
+        'headline',
+        'view',
+        'formatter configuration',
+      ],
+    ];
+
+  }
+
+  /**
+   * Tests MassageOut.
+   *
+   * @covers ::massageOut()
+   *
+   * @dataProvider providerTestMassageOut
+   */
+  public function testMassageOut($properties, $display_context, $expected) {
+    $properties = [
+      'content' => [
+        'title' => 'foo',
+        'headline' => 'foo',
+      ],
+      'hidden' => [
+        'title' => 'bar',
+        'headline' => 'bar',
+      ],
+      'baz' => [
+        'title' => 'cat',
+        'headline' => 'dog',
+      ],
+    ];
+
+    $this->handler->setContext([
+      'entity_type' => 'anything',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'massageOut');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, [$properties]);
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testGetDisplayableField().
+   */
+  public function providerTestMassageOut() {
+    $properties = [
+      'content' => [
+        'title' => 'foo',
+        'headline' => 'foo',
+      ],
+      'hidden' => [
+        'title' => 'bar',
+        'headline' => 'bar',
+      ],
+      'baz' => [
+        'title' => 'cat',
+        'headline' => 'dog',
+      ],
+    ];
+    return [
+      'no context' => [
+        'not_exist',
+        'no_context',
+        $properties,
+      ],
+      'text context' => [
+        'title',
+        'form',
+        [
+          'content' => [
+            'headline' => 'foo',
+          ],
+          'hidden' => [
+            'headline' => 'bar',
+          ],
+          'baz' => [
+            'title' => 'cat',
+            'headline' => 'dog',
+          ],
+        ],
+      ],
+      'headline context' => [
+        'headline',
+        'view',
+        [
+          'content' => [
+            'title' => 'foo',
+          ],
+          'hidden' => [
+            'title' => 'bar',
+          ],
+          'baz' => [
+            'title' => 'cat',
+            'headline' => 'dog',
+          ],
+        ],
+      ],
+    ];
+  }
+
+  /**
+   * Tests getRenderer.
+   *
+   * @covers ::getRenderer()
+   *
+   * @dataProvider providerTestGetRenderer
+   */
+  public function testGetRenderer($options, $display_context, $name, $expected) {
+    if ($display_context == 'view') {
+      $this->formatterPluginManager->expects($this->any())
+        ->method('getInstance')
+        ->willReturn($expected);
+    }
+    else {
+      $this->widgetPluginManager->expects($this->any())
+        ->method('getInstance')
+        ->willReturn($expected);
+    }
+
+    $this->handler->setContext([
+      'entity_type' => 'foo',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+      'mode' => 'cat',
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'getRenderer');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, [$name, $options]);
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testGetRenderer().
+   */
+  public function providerTestGetRenderer() {
+    return [
+      'no type' => [
+        [],
+        'no_name',
+        'no_name',
+        NULL,
+      ],
+      'form' => [
+        ['type' => 'text'],
+        'form',
+        'title',
+        $this->getMockBuilder(StringTextfieldWidget::class)
+          ->disableOriginalConstructor()
+          ->getMock(),
+      ],
+      'view' => [
+        ['type' => 'text'],
+        'view',
+        'headline',
+        $this->getMockBuilder(TextDefaultFormatter::class)
+          ->disableOriginalConstructor()
+          ->getMock(),
+      ],
+    ];
+  }
+
+  /**
+   * Tests hasElement.
+   *
+   * @covers ::hasElement()
+   *
+   * @dataProvider providerTestHasElement
+   */
+  public function testHasElement($display_context, $name, $expected) {
+    $this->handler->setContext([
+      'entity_type' => 'foo',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'hasElement');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, [$name]);
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testHasElement().
+   */
+  public function providerTestHasElement() {
+    return [
+      'no context' => [
+        'no_context',
+        '',
+        FALSE,
+      ],
+      'form' => [
+        'form',
+        'title',
+        TRUE,
+      ],
+      'view' => [
+        'view',
+        'headline',
+        TRUE,
+      ],
+    ];
+  }
+
+  /**
+   * Tests getFieldDefinition.
+   *
+   * @covers ::getFieldDefinition()
+   *
+   * @dataProvider providerTestGetFieldDefinition
+   */
+  public function testGetFieldDefinition($display_context, $expected_name) {
+    $this->handler->setContext([
+      'entity_type' => 'foo',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'getFieldDefinition');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, [$expected_name]);
+    $expected = $expected_name;
+    if (!empty($expected_name)) {
+      $expected = $this->definitions[$expected_name];
+    }
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testGetFieldDefinition().
+   */
+  public function providerTestGetFieldDefinition() {
+    return [
+      'no context' => [
+        'no_context',
+        NULL,
+      ],
+      'form' => [
+        'form',
+        'title',
+      ],
+      'view' => [
+        'view',
+        'headline',
+      ],
+    ];
+  }
+
+  /**
+   * Tests getDisplayableFields.
+   *
+   * @covers ::getDisplayableFields()
+   *
+   * @dataProvider providerTestGetDisplayableField
+   */
+  public function testGetDisplayableField($display_context, $expected_name) {
+    $this->handler->setContext([
+      'entity_type' => 'foo',
+      'bundle' => 'bar',
+      'display_context' => $display_context,
+    ]);
+
+    $testMethod = new \ReflectionMethod(FieldDisplayComponentHandler::class, 'getDisplayableFields');
+    $testMethod->setAccessible(TRUE);
+    $actual = $testMethod->invokeArgs($this->handler, []);
+    if (empty($expected_name)) {
+      $expected = $expected_name;
+    }
+    else {
+      $expected[$expected_name] = $this->definitions[$expected_name];
+    }
+    $this->assertEquals($expected, $actual);
+  }
+
+  /**
+   * Provides data for testGetDisplayableField().
+   */
+  public function providerTestGetDisplayableField() {
+    return [
+      'no context' => [
+        'no_context',
+        [],
+      ],
+      'form' => [
+        'form',
+        'title',
+      ],
+      'view' => [
+        'view',
+        'headline',
+      ],
+    ];
+  }
+
+  /**
+   * Helper to set field definitions for all tests.
+   */
+  public function getTestFieldDefinitions() {
+    $title = clone($this->definition);
+    $headline = clone($this->definition);
+
+    return [
+      'no_display' => $this->definition,
+      'headline' => $headline->setDisplayOptions('view', ['label' => 'above']),
+      'title' => $title->setDisplayOptions('form', ['label' => 'above']),
+    ];
+  }
+
+}
only in patch2:
unchanged:
--- a/core/tests/Drupal/Tests/Core/Entity/Access/EntityFormDisplayAccessControlHandlerTest.php
+++ b/core/tests/Drupal/Tests/Core/Entity/Access/EntityFormDisplayAccessControlHandlerTest.php
@@ -7,6 +7,7 @@
 use Drupal\Core\Cache\Context\CacheContextsManager;
 use Drupal\Core\Config\Entity\ConfigEntityTypeInterface;
 use Drupal\Core\DependencyInjection\Container;
+use Drupal\Core\Entity\DisplayComponentHandlerPluginManager;
 use Drupal\Core\Entity\Entity\Access\EntityFormDisplayAccessControlHandler;
 use Drupal\Core\Entity\Entity\EntityFormDisplay;
 use Drupal\Core\Entity\EntityFieldManagerInterface;
@@ -182,6 +183,7 @@ protected function setUp(): void {
     $container->set('uuid', $this->createMock(UuidInterface::class));
     $container->set('renderer', $this->createMock(RendererInterface::class));
     $container->set('cache_contexts_manager', $this->prophesize(CacheContextsManager::class));
+    $container->set('plugin.manager.entity.display_component_handler', $this->prophesize(DisplayComponentHandlerPluginManager::class));
     \Drupal::setContainer($container);
 
     $this->entity = new EntityFormDisplay([