diff --git a/core/modules/serialization/src/Normalizer/TypedDataNormalizer.php b/core/modules/serialization/src/Normalizer/TypedDataNormalizer.php
index 690fd8db25..4a94f7086c 100644
--- a/core/modules/serialization/src/Normalizer/TypedDataNormalizer.php
+++ b/core/modules/serialization/src/Normalizer/TypedDataNormalizer.php
@@ -18,13 +18,9 @@ class TypedDataNormalizer extends NormalizerBase {
    * {@inheritdoc}
    */
   public function normalize($object, $format = NULL, array $context = []) {
+    /* @var \Drupal\Core\TypedData\TypedDataInterface $object */
     $this->addCacheableDependency($context, $object);
-    $value = $object->getValue();
-    // Support for stringable value objects: avoid numerous custom normalizers.
-    if (is_object($value) && method_exists($value, '__toString')) {
-      $value = (string) $value;
-    }
-    return $value;
+    return $object->getString();
   }
 
 }
diff --git a/core/modules/text/src/TextProcessed.php b/core/modules/text/src/TextProcessed.php
index 1e3c880d58..9755146ed6 100644
--- a/core/modules/text/src/TextProcessed.php
+++ b/core/modules/text/src/TextProcessed.php
@@ -25,11 +25,11 @@ class TextProcessed extends TypedData implements CacheableDependencyInterface {
   protected $value = NULL;
 
   /**
-   * Whether the property's value has already been computed or not.
+   * The render build that was used to compute the field.
    *
-   * @var bool
+   * @var array
    */
-  protected $valueComputed = FALSE;
+  protected $computedBuild;
 
   /**
    * {@inheritdoc}
@@ -46,9 +46,10 @@ public function __construct(DataDefinitionInterface $definition, $name = NULL, T
    * Ensures that values are only computed once.
    */
   protected function ensureComputedValue() {
-    if ($this->valueComputed === FALSE) {
+    $build = $this->getRenderBuild();
+    if ($build !== $this->computedBuild) {
       $this->computeValue();
-      $this->valueComputed = TRUE;
+      $this->computedBuild = $build;
     }
   }
 
@@ -64,23 +65,13 @@ public function getValue() {
    * {@inheritdoc}
    */
   protected function computeValue() {
-    /** @var \Drupal\Core\Field\FieldItemInterface $item */
-    $item = $this->getParent();
-    $text = $item->{($this->definition->getSetting('text source'))};
-
+    $build = $this->getRenderBuild();
     // Avoid running \Drupal\Core\Render\RendererInterface::renderPlain
     // on empty strings.
-    if (!isset($text) || $text === '') {
+    if (!isset($build['#text']) || $build['#text'] === '') {
       $this->value = new FilterProcessResult('');
     }
     else {
-      $build = [
-        '#type' => 'processed_text',
-        '#text' => $text,
-        '#format' => $item->format,
-        '#filter_types_to_skip' => [],
-        '#langcode' => $item->getLangcode(),
-      ];
       // Capture the cacheability metadata associated with the processed text.
       $processed_text = $this->getRenderer()->renderPlain($build);
       $this->value = FilterProcessResult::createFromRenderArray($build)->setProcessedText((string) $processed_text);
@@ -120,4 +111,24 @@ protected function getRenderer() {
     return \Drupal::service('renderer');
   }
 
+  /**
+   * Gets the render build for the processed value.
+   *
+   * @return array
+   *   The render array.
+   */
+  protected function getRenderBuild(): array {
+    /** @var \Drupal\Core\Field\FieldItemInterface $item */
+    $item = $this->getParent();
+    $text = $item->{($this->definition->getSetting('text source'))};
+    $build = [
+      '#type' => 'processed_text',
+      '#text' => $text,
+      '#format' => $item->format,
+      '#filter_types_to_skip' => [],
+      '#langcode' => $item->getLangcode(),
+    ];
+    return $build;
+  }
+
 }
diff --git a/core/modules/text/tests/src/Kernel/TextWithSummaryItemTest.php b/core/modules/text/tests/src/Kernel/TextWithSummaryItemTest.php
index fa9db4018d..a48c191b5e 100644
--- a/core/modules/text/tests/src/Kernel/TextWithSummaryItemTest.php
+++ b/core/modules/text/tests/src/Kernel/TextWithSummaryItemTest.php
@@ -81,8 +81,6 @@ public function testCrudAndUpdate() {
 
     // Change the format, this should update the processed properties.
     $entity->summary_field->format = 'no_filters';
-    $entity->save();
-    $entity = $storage->load($entity->id());
     $this->assertEqual($entity->summary_field->processed, $value);
     $this->assertEqual($entity->summary_field->summary_processed, $summary);