diff --git a/core/lib/Drupal/Core/Config/TypedConfigManager.php b/core/lib/Drupal/Core/Config/TypedConfigManager.php
index 822830e..647d00f 100644
--- a/core/lib/Drupal/Core/Config/TypedConfigManager.php
+++ b/core/lib/Drupal/Core/Config/TypedConfigManager.php
@@ -91,13 +91,8 @@ public function get($name) {
    */
   public function create(array $definition, $value = NULL, $name = NULL, $parent = NULL) {
     if (!isset($definition['type'])) {
-      // Set default type 'string' if possible. If not it will be 'undefined'.
-      if (is_string($value)) {
-        $definition['type'] = 'string';
-      }
-      else {
-        $definition['type'] = 'undefined';
-      }
+      // By default elements without a type are undefined.
+      $definition['type'] = 'undefined';
     }
     elseif (strpos($definition['type'], ']')) {
       // Replace variable names in definition.