diff --git a/core/lib/Drupal/Core/Layout/LayoutDefinition.php b/core/lib/Drupal/Core/Layout/LayoutDefinition.php
index a9fe407e83..e3d0488929 100644
--- a/core/lib/Drupal/Core/Layout/LayoutDefinition.php
+++ b/core/lib/Drupal/Core/Layout/LayoutDefinition.php
@@ -181,13 +181,13 @@ public function set($property, $value) {
    *   The human-readable name of the layout definition.
    */
   public function getLabel() {
-    return new TranslatableMarkup($this->label);
+    return $this->label instanceof TranslatableMarkup ? $this->label : new TranslatableMarkup($this->label);
   }
 
   /**
    * Sets the human-readable name of the layout definition.
    *
-   * @param \Drupal\Core\StringTranslation\TranslatableMarkup $label
+   * @param string|\Drupal\Core\StringTranslation\TranslatableMarkup $label
    *   The human-readable name of the layout definition.
    *
    * @return $this
@@ -204,7 +204,7 @@ public function setLabel($label) {
    *   The description of the layout definition.
    */
   public function getDescription() {
-    return new TranslatableMarkup($this->description);
+    return $this->description instanceof TranslatableMarkup ? $this->description : new TranslatableMarkup($this->description);
   }
 
   /**
@@ -227,7 +227,7 @@ public function setDescription($description) {
    *   The human-readable category of the layout definition.
    */
   public function getCategory() {
-    return new TranslatableMarkup($this->category);
+    return $this->category instanceof TranslatableMarkup ? $this->category : new TranslatableMarkup($this->category);
   }
 
   /**