diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index bca41086fa405c43282cac37e99a5f744630c562..a740e57d0f0a912a98bfb729a1ef24292d759647 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -832,8 +832,8 @@ function comment_form_field_ui_field_instance_edit_form_alter(&$form, $form_stat
  * Implements hook_form_FORM_ID_alter().
  */
 function comment_form_field_ui_field_overview_form_alter(&$form, $form_state) {
-  if ($form['#entity_type'] == 'comment') {
-    $request = \Drupal::request();
+  $request = \Drupal::request();
+  if ($form['#entity_type'] == 'comment' && $request->attributes->has('commented_entity_type')) {
     $form['#title'] = \Drupal::service('comment.manager')->getFieldUIPageTitle($request->attributes->get('commented_entity_type'), $request->attributes->get('field_name'));
   }
 }
@@ -842,8 +842,8 @@ function comment_form_field_ui_field_overview_form_alter(&$form, $form_state) {
  * Implements hook_form_FORM_ID_alter().
  */
 function comment_form_field_ui_form_display_overview_form_alter(&$form, $form_state) {
-  if ($form['#entity_type'] == 'comment') {
-    $request = \Drupal::request();
+  $request = \Drupal::request();
+  if ($form['#entity_type'] == 'comment' && $request->attributes->has('commented_entity_type')) {
     $form['#title'] = \Drupal::service('comment.manager')->getFieldUIPageTitle($request->attributes->get('commented_entity_type'), $request->attributes->get('field_name'));
   }
 }
@@ -852,8 +852,8 @@ function comment_form_field_ui_form_display_overview_form_alter(&$form, $form_st
  * Implements hook_form_FORM_ID_alter().
  */
 function comment_form_field_ui_display_overview_form_alter(&$form, $form_state) {
-  if ($form['#entity_type'] == 'comment') {
-    $request = \Drupal::request();
+  $request = \Drupal::request();
+  if ($form['#entity_type'] == 'comment' && $request->attributes->has('commented_entity_type')) {
     $form['#title'] = \Drupal::service('comment.manager')->getFieldUIPageTitle($request->attributes->get('commented_entity_type'), $request->attributes->get('field_name'));
   }
 }
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentFieldsTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentFieldsTest.php
index 8f34413476faf910c20da7b7980235a213941370..0e69739554823f4144a3f29dfb5fee5e69e50bb9 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentFieldsTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentFieldsTest.php
@@ -123,6 +123,12 @@ function testCommentFormat() {
     $edit = array('instance[settings][text_processing]' => 0);
     $this->drupalPostForm('admin/structure/comments/manage/node__comment/fields/comment.node__comment.comment_body', $edit, t('Save settings'));
 
+    // Change formatter settings.
+    $this->drupalGet('admin/structure/comments/manage/node__comment/display');
+    $edit = array('fields[comment_body][type]' => 'text_trimmed', 'refresh_rows' => 'comment_body');
+    $commands = $this->drupalPostAjaxForm(NULL, $edit, array('op' => t('Refresh')));
+    $this->assertTrue($commands, 'Ajax commands returned');
+
     // Post a comment without an explicit subject.
     $this->drupalLogin($this->web_user);
     $edit = array('comment_body[0][value]' => $this->randomName(8));
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentTestBase.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentTestBase.php
index 5a88dd679d6596ba238111b114d315e3aa39a0f0..d3fc90a2ace0291f0934d21c57d40f04a18a2d26 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentTestBase.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentTestBase.php
@@ -59,6 +59,7 @@ function setUp() {
       'administer content types',
       'administer comments',
       'administer comment fields',
+      'administer comment display',
       'skip comment approval',
       'post comments',
       'access comments',