diff --git a/core/lib/Drupal/Component/Serialization/TaggedSerializationTrait.php b/core/lib/Drupal/Component/Serialization/TaggedSerializationTrait.php
index 837c04b188..8253479841 100644
--- a/core/lib/Drupal/Component/Serialization/TaggedSerializationTrait.php
+++ b/core/lib/Drupal/Component/Serialization/TaggedSerializationTrait.php
@@ -14,6 +14,28 @@ trait TaggedSerializationTrait {
    */
   protected static $tagCallbacks = [];
 
+  /**
+   * Executes a tag callback.
+   *
+   * @param mixed $value
+   *   The parsed value.
+   * @param string $tag
+   *   The tag name.
+   *
+   * @return mixed
+   *   Result from the callback or original $value if no callback exists.
+   */
+  public static function executeTagCallback($value, $tag) {
+    $callbacks = static::getTagCallbacks();
+
+    // Immediately return the original value if there is no callback.
+    if (!isset($callbacks[$tag])) {
+      return $value;
+    }
+
+    return $callbacks[$tag](...(array) $value);
+  }
+
   /**
    * Retrieves a map of tag callbacks.
    *
@@ -22,7 +44,22 @@ trait TaggedSerializationTrait {
    *   callback.
    */
   public static function getTagCallbacks() {
-    return [];
+    return static::$tagCallbacks;
+  }
+
+  /**
+   * Merges tag callbacks from this serializer onto a target serializer.
+   *
+   * @param string|\Drupal\Component\Serialization\TaggedSerializationInterface $serializer
+   *   The target serializer to merge tag callbacks onto.
+   */
+  protected static function mergeTagCallbacks($serializer) {
+    if ($serializer instanceof TaggedSerializationInterface || is_subclass_of($serializer, TaggedSerializationInterface::class)) {
+      $serializer::setTagCallbacks(array_merge(
+        $serializer::getTagCallbacks(),
+        static::getTagCallbacks()
+      ));
+    }
   }
 
   /**
diff --git a/core/lib/Drupal/Component/Serialization/Yaml.php b/core/lib/Drupal/Component/Serialization/Yaml.php
index 3889dd36f4..ec41c3accc 100644
--- a/core/lib/Drupal/Component/Serialization/Yaml.php
+++ b/core/lib/Drupal/Component/Serialization/Yaml.php
@@ -59,11 +59,9 @@ protected static function getSerializer() {
         // Otherwise, fallback to the Symfony implementation.
         static::$serializer = YamlSymfony::class;
       }
+
       // Merge the tag callbacks from this proxy to the chosen serializer.
-      static::$serializer::setTagCallbacks(array_merge(
-        static::$serializer::getTagCallbacks(),
-        static::getTagCallbacks()
-      ));
+      static::mergeTagCallbacks(static::$serializer);
     }
     return static::$serializer;
   }
diff --git a/core/lib/Drupal/Component/Serialization/YamlSymfony.php b/core/lib/Drupal/Component/Serialization/YamlSymfony.php
index 2ea01d4ba2..ae6fce4f8b 100644
--- a/core/lib/Drupal/Component/Serialization/YamlSymfony.php
+++ b/core/lib/Drupal/Component/Serialization/YamlSymfony.php
@@ -45,12 +45,9 @@ public static function decode($raw) {
       }
 
       // Support Symfony 3.3 TaggedValue objects.
-      array_walk_recursive($data, function (&$value) {
-        if ($value instanceof TaggedValue) {
-          $callbacks = static::getTagCallbacks();
-          $args = (array) $value->getValue();
-          $tag = $value->getTag();
-          return isset($callbacks[$tag]) ? $callbacks[$tag](...$args) : $args;
+      array_walk_recursive($data, function (&$item) {
+        if ($item instanceof TaggedValue) {
+          $item = static::executeTagCallback($item->getValue(), '!' . $item->getTag());
         }
       });
 
diff --git a/core/lib/Drupal/Core/Serialization/Yaml.php b/core/lib/Drupal/Core/Serialization/Yaml.php
index 1b089249cf..392b6fe86b 100644
--- a/core/lib/Drupal/Core/Serialization/Yaml.php
+++ b/core/lib/Drupal/Core/Serialization/Yaml.php
@@ -32,10 +32,7 @@ protected static function getSerializer() {
 
       // Merge the tag callbacks from this proxy to the chosen serializer.
       if (static::$serializer instanceof TaggedSerializationInterface) {
-        static::$serializer::setTagCallbacks(array_merge(
-          static::$serializer::getTagCallbacks(),
-          static::getTagCallbacks()
-        ));
+        static::mergeTagCallbacks(static::$serializer);
       }
     }
     return parent::getSerializer();