diff --git a/core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php b/core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php
index 9a35f90..e5fa4ba 100644
--- a/core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php
+++ b/core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php
@@ -105,15 +105,20 @@ public static function create(ContainerInterface $container, array $configuratio
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
-    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
+  public function form(FieldItemListInterface $items, array &$form, FormStateInterface $form_state, $get_delta = NULL) {
     $entity = $items->getEntity();
-
-    /* @var \Drupal\Core\Config\Entity\ConfigEntityInterface $bundle_entity */
     if (!$this->moderationInformation->isModeratedEntity($entity)) {
-      // @todo https://www.drupal.org/node/2779933 write a test for this.
-      return $element + ['#access' => FALSE];
+      return [];
     }
+    return parent::form($items, $form, $form_state, $get_delta);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
+    /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
+    $entity = $items->getEntity();
 
     $workflow = $this->moderationInformation->getWorkflowForEntity($entity);
     $default = $items->get($delta)->value ? $workflow->getTypePlugin()->getState($items->get($delta)->value) : $workflow->getTypePlugin()->getInitialState($workflow, $entity);
diff --git a/core/modules/content_moderation/tests/src/Kernel/ModerationStateWidgetTest.php b/core/modules/content_moderation/tests/src/Kernel/ModerationStateWidgetTest.php
new file mode 100644
index 0000000..76d797d
--- /dev/null
+++ b/core/modules/content_moderation/tests/src/Kernel/ModerationStateWidgetTest.php
@@ -0,0 +1,78 @@
+<?php
+
+namespace Drupal\Tests\content_moderation\Kernel;
+
+use Drupal\Core\Entity\Entity\EntityFormDisplay;
+use Drupal\Core\Form\FormState;
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\node\Entity\Node;
+use Drupal\node\Entity\NodeType;
+use Drupal\workflows\Entity\Workflow;
+
+/**
+ * @coversDefaultClass \Drupal\content_moderation\Plugin\Field\FieldWidget\ModerationStateWidget
+ * @group content_moderation
+ */
+class ModerationStateWidgetTest extends KernelTestBase {
+
+  /**
+   * Modules to install.
+   *
+   * @var array
+   */
+  public static $modules = [
+    'system',
+    'user',
+    'workflows',
+    'content_moderation',
+    'node',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installEntitySchema('content_moderation_state');
+    $this->installEntitySchema('user');
+    $this->installConfig(['content_moderation', 'system']);
+
+    NodeType::create([
+      'type' => 'moderated',
+    ])->save();
+    NodeType::create([
+      'type' => 'unmoderated',
+    ])->save();
+
+    $workflow = Workflow::load('editorial');
+    $workflow->getTypePlugin()->addEntityTypeAndBundle('node', 'moderated');
+    $workflow->save();
+  }
+
+  /**
+   * Test the widget does not impact a non-moderated entity.
+   */
+  public function testWidgetNonModeratedEntity() {
+    // Create an unmoderated entity and build a form display which will include
+    // the ModerationStateWidget plugin, in a hidden state.
+    $entity = Node::create([
+      'type' => 'unmoderated',
+    ]);
+    $entity_form_display = EntityFormDisplay::create([
+      'targetEntityType' => 'node',
+      'bundle' => 'unmoderated',
+      'mode' => 'default',
+      'status' => TRUE,
+    ]);
+    $form = [];
+    $form_state = new FormState();
+    $entity_form_display->buildForm($entity, $form, $form_state);
+
+    // The moderation_state field should have no values for an entity that isn't
+    // being moderated.
+    $entity_form_display->extractFormValues($entity, $form, $form_state);
+    $this->assertEquals(0, $entity->moderation_state->count());
+  }
+
+}