diff --git a/core/lib/Drupal/Core/Field/FieldItemList.php b/core/lib/Drupal/Core/Field/FieldItemList.php
index bbcd55f..02ba043 100644
--- a/core/lib/Drupal/Core/Field/FieldItemList.php
+++ b/core/lib/Drupal/Core/Field/FieldItemList.php
@@ -122,7 +122,7 @@ public function setValue($values, $notify = TRUE) {
    * {@inheritdoc}
    */
   public function getSerializationValue($deep_serialization) {
-    return $this->getValue();
+    return $this->getValue($deep_serialization);
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/LanguageItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/LanguageItem.php
index 18935c1..52a3f34 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/LanguageItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/LanguageItem.php
@@ -52,6 +52,27 @@ public static function propertyDefinitions(FieldStorageDefinitionInterface $fiel
   }
 
   /**
+   * {@inheritdoc}
+   */
+  public function getValue($include_computed = FALSE) {
+    $value = parent::getValue();
+
+    // Include computed properties if the condition of
+    // ::includeComputedProperties() is fulfilled.
+    if ($this->includeComputedProperties($include_computed)) {
+      // Iterate only over computed properties and include them, as the parent
+      // method is not including them.
+      foreach ($this->properties as $name => $property) {
+        $definition = $property->getDataDefinition();
+        if ($definition->isComputed()) {
+          $value[$name] = $property->getValue();
+        }
+      }
+    }
+    return $value;
+  }
+
+  /**
    * Defines allowed language codes for the field's AllowedValues constraint.
    *
    * @return string[]
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntitySerializationTest.php b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntitySerializationTest.php
index c109886..f40d4ed 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntitySerializationTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntitySerializationTest.php
@@ -4,6 +4,7 @@
 
 use Drupal\field\Entity\FieldConfig;
 use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\language\Entity\ConfigurableLanguage;
 
 /**
  * Tests the serialization of content entities.
@@ -17,7 +18,7 @@ class ContentEntitySerializationTest extends EntityKernelTestBase {
    *
    * @var array
    */
-  public static $modules = ['user', 'system', 'field', 'entity_test'];
+  public static $modules = ['user', 'system', 'field', 'entity_test', 'language'];
 
   /**
    * The entity type id.
@@ -46,6 +47,7 @@ class ContentEntitySerializationTest extends EntityKernelTestBase {
   protected function setUp() {
     parent::setUp();
     $this->installEntitySchema($this->entityTypeId);
+    $this->installConfig('language');
     $this->entityStorage = $this->entityManager->getStorage($this->entityTypeId);
 
     // Create the test entity reference field.
@@ -108,6 +110,19 @@ protected function doTestSerialization($deep_serialization) {
     $entity_level_zero->$field_name->entity->name = 'entity level one';
     $entity_level_zero->$field_name->entity->$field_name->entity->name = 'entity level two';
 
+    // Alter a computed property beside the entity property in order to assure
+    // that all computed properties are being serialized through deep
+    // serialization.
+    $entity_type = $entity_level_two->getEntityType();
+    $this->assertTrue($entity_type->hasKey('langcode'));
+    $langcode_field_name = $entity_type->getKey('langcode');
+    $langcode_field = $entity_level_zero->$field_name->entity->$field_name->entity->$langcode_field_name;
+    $test_language = ConfigurableLanguage::load($langcode_field->language->getId());
+    $original_language_name = $test_language->getName();
+    $test_language->setName('test deep serialization on language property');
+    $langcode_field->language = $test_language;
+    $this->assertEquals('test deep serialization on language property', $langcode_field->language->getName());
+
     if ($deep_serialization) {
       $entity_level_zero->setDeepSerialization(TRUE);
     }
@@ -122,6 +137,8 @@ protected function doTestSerialization($deep_serialization) {
     $this->assertEquals('entity level zero', $entity_level_zero->label());
     $this->assertEquals($deep_serialization ? 'entity level one' : $initial_entity_name, $entity_level_zero->$field_name->entity->label());
     $this->assertEquals($deep_serialization ? 'entity level two' : $initial_entity_name, $entity_level_zero->$field_name->entity->$field_name->entity->label());
+    $language = $entity_level_zero->$field_name->entity->$field_name->entity->$langcode_field_name->language;
+    $this->assertEquals($deep_serialization ? 'test deep serialization on language property' : $original_language_name, $language->getName());
   }
 
 }