core/lib/Drupal/Core/Render/Renderer.php                       |  2 +-
 core/modules/big_pipe/src/Render/BigPipe.php                   |  5 +++--
 .../tests/src/FunctionalJavascript/BigPipeRegressionTest.php   | 10 ++--------
 .../src/RenderPlaceholderMessageTestController.php             |  1 -
 4 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/core/lib/Drupal/Core/Render/Renderer.php b/core/lib/Drupal/Core/Render/Renderer.php
index 4e98db7..a624c0f 100644
--- a/core/lib/Drupal/Core/Render/Renderer.php
+++ b/core/lib/Drupal/Core/Render/Renderer.php
@@ -653,7 +653,7 @@ protected function replacePlaceholders(array &$elements) {
       return FALSE;
     }
 
-    // The 'status messages' placeholder' needs to be special cased, because it
+    // The 'status messages' placeholder needs to be special cased, because it
     // depends on global state that can be modified when other placeholders are
     // being rendered: any code can add messages to render.
     // This violates the principle that each lazy builder must be able to render
diff --git a/core/modules/big_pipe/src/Render/BigPipe.php b/core/modules/big_pipe/src/Render/BigPipe.php
index 5b45678..00ec4a2 100644
--- a/core/modules/big_pipe/src/Render/BigPipe.php
+++ b/core/modules/big_pipe/src/Render/BigPipe.php
@@ -547,7 +547,7 @@ protected function getPlaceholderOrder($html) {
     }
     $placeholders = array_unique($placeholders);
 
-    // The 'status messages' placeholder' needs to be special cased, because it
+    // The 'status messages' placeholder needs to be special cased, because it
     // depends on global state that can be modified when other placeholders are
     // being rendered: any code can add messages to render.
     // This violates the principle that each lazy builder must be able to render
@@ -567,7 +567,8 @@ protected function getPlaceholderOrder($html) {
       'callback=Drupal%5CCore%5CRender%5CElement%5CStatusMessages%3A%3ArenderMessages&args[0]=error&token=35b549cb',
     ];
 
-    // Render placeholders in the appropriate order.
+    // Return placeholder IDs in DOM order, but with the 'status messages' at
+    // the end, if it exists.
     $ordered_placeholders = array_merge(
       array_diff($placeholders, $possible_message_placeholders),
       array_intersect($placeholders, $possible_message_placeholders)
diff --git a/core/modules/big_pipe/tests/src/FunctionalJavascript/BigPipeRegressionTest.php b/core/modules/big_pipe/tests/src/FunctionalJavascript/BigPipeRegressionTest.php
index addda90..3243345 100644
--- a/core/modules/big_pipe/tests/src/FunctionalJavascript/BigPipeRegressionTest.php
+++ b/core/modules/big_pipe/tests/src/FunctionalJavascript/BigPipeRegressionTest.php
@@ -48,13 +48,7 @@ public function setUp() {
    * @see https://www.drupal.org/node/2698811
    */
   public function testCommentForm_2698811() {
-    $this->assertTrue($this->container->get('module_installer')->install([    'node',
-      'comment',
-      'history',
-      'editor',
-      'ckeditor',
-      'filter',
-    ], TRUE), 'Installed modules.');
+    $this->assertTrue($this->container->get('module_installer')->install(['comment', 'history', 'ckeditor'], TRUE), 'Installed modules.');
 
     // Ensure an `article` node type exists.
     $this->createContentType(['type' => 'article']);
@@ -118,7 +112,7 @@ public function testCommentForm_2698811() {
   }
 
   /**
-   * Ensure BigPipe renders the "messages" placeholder last.
+   * Ensure messages set in placeholders always appear.
    *
    * @see https://www.drupal.org/node/2712935
    */
diff --git a/core/modules/system/tests/modules/render_placeholder_message_test/src/RenderPlaceholderMessageTestController.php b/core/modules/system/tests/modules/render_placeholder_message_test/src/RenderPlaceholderMessageTestController.php
index 7aeaadb..f02f0b6 100644
--- a/core/modules/system/tests/modules/render_placeholder_message_test/src/RenderPlaceholderMessageTestController.php
+++ b/core/modules/system/tests/modules/render_placeholder_message_test/src/RenderPlaceholderMessageTestController.php
@@ -70,7 +70,6 @@ protected function build(array $placeholder_order) {
       return $renderer->render($build, FALSE);
     });
 
-
     $reordered = [];
     foreach ($placeholder_order as $placeholder) {
       $reordered[$placeholder] = $build['#attached']['placeholders'][$placeholder];