diff -u b/core/lib/Drupal/Component/Utility/ReadOnlyArrayIterator.php b/core/lib/Drupal/Component/Utility/ReadOnlyArrayIterator.php
--- b/core/lib/Drupal/Component/Utility/ReadOnlyArrayIterator.php
+++ b/core/lib/Drupal/Component/Utility/ReadOnlyArrayIterator.php
@@ -14,7 +14,7 @@
    */
   public function offsetGet($index) {
     $value = parent::offsetGet($index);
-    if (is_array($value)) {
+    if (is_array($value) && !empty($value)) {
       $value = new ReadOnlyArrayObject($value);
     }
     return $value;
@@ -25,7 +25,7 @@
    */
   public function current() {
     $value = parent::current();
-    if (is_array($value)) {
+    if (is_array($value) && !empty($value)) {
       $value = new ReadOnlyArrayObject($value);
     }
     return $value;
diff -u b/core/lib/Drupal/Component/Utility/ReadOnlyArrayObject.php b/core/lib/Drupal/Component/Utility/ReadOnlyArrayObject.php
--- b/core/lib/Drupal/Component/Utility/ReadOnlyArrayObject.php
+++ b/core/lib/Drupal/Component/Utility/ReadOnlyArrayObject.php
@@ -14,7 +14,7 @@
    */
   public function offsetGet($index) {
     $value = parent::offsetGet($index);
-    if (is_array($value)) {
+    if (is_array($value) && !empty($value)) {
       $value = new ReadOnlyArrayObject($value);
     }
     return $value;
diff -u b/core/lib/Drupal/Core/Template/TwigEnvironment.php b/core/lib/Drupal/Core/Template/TwigEnvironment.php
--- b/core/lib/Drupal/Core/Template/TwigEnvironment.php
+++ b/core/lib/Drupal/Core/Template/TwigEnvironment.php
@@ -154,7 +154,7 @@
   public function wrapContext(&$context) {
     if (is_array($context)) {
       foreach ($context as $key => $value) {
-        if (is_array($context[$key])) {
+        if (is_array($context[$key]) && !empty($context[$key])) {
           $context[$key] = new ReadOnlyArrayObject($context[$key]);
         }
       }