diff --git a/core/lib/Drupal/Core/Render/Element/Textarea.php b/core/lib/Drupal/Core/Render/Element/Textarea.php
index efeebcd..ff6186c 100644
--- a/core/lib/Drupal/Core/Render/Element/Textarea.php
+++ b/core/lib/Drupal/Core/Render/Element/Textarea.php
@@ -60,7 +60,7 @@ public function getInfo() {
    * {@inheritdoc}
    */
   public static function valueCallback(&$element, $input, FormStateInterface $form_state) {
-    if ($input !== FALSE && $input !== NULL) {
+    if ($input !== FALSE) {
       // This should be a string, but allow other scalars since they might be
       // valid input in programmatic form submissions.
       return is_scalar($input) ? (string) $input : '';