diff --git a/core/modules/comment/lib/Drupal/comment/CommentFormController.php b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
index f0f16c2..8e7c7f6 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentFormController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
@@ -64,7 +64,6 @@ class CommentFormController extends EntityFormController {
     if ($is_admin) {
       $author = (!$comment->uid && $comment->name ? $comment->name : $comment->registered_name);
       $status = (isset($comment->status) ? $comment->status : COMMENT_NOT_PUBLISHED);
-      $date = (!empty($comment->date) ? $comment->date : format_date($comment->created, 'custom', 'Y-m-d H:i O'));
     }
     else {
       if ($user->uid) {
@@ -74,7 +73,11 @@ class CommentFormController extends EntityFormController {
         $author = ($comment->name ? $comment->name : '');
       }
       $status = (user_access('skip comment approval') ? COMMENT_PUBLISHED : COMMENT_NOT_PUBLISHED);
-      $date = '';
+    }
+
+    $date = '';
+    if(!empty($comment->cid)) {
+      $date = (!empty($comment->date) ? $comment->date : format_date($comment->created, 'custom', 'Y-m-d H:i:s O'));
     }
 
     // Add the author name field depending on the current user.
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentPreviewTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentPreviewTest.php
index 10dc207..2f49bf1 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentPreviewTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentPreviewTest.php
@@ -85,7 +85,7 @@ class CommentPreviewTest extends CommentTestBase {
     $edit['date'] = '2008-03-02 17:23 +0300';
     $raw_date = strtotime($edit['date']);
     $expected_text_date = format_date($raw_date);
-    $expected_form_date = format_date($raw_date, 'custom', 'Y-m-d H:i O');
+    $expected_form_date = format_date($raw_date, 'custom', 'Y-m-d H:i:s O');
     $comment = $this->postComment($this->node, $edit['subject'], $edit['comment_body[' . $langcode . '][0][value]'], TRUE);
     $this->drupalPost('comment/' . $comment->id . '/edit', $edit, t('Preview'));