diff -u b/core/modules/node/lib/Drupal/node/Tests/NodeFieldMultilingualTestCase.php b/core/modules/node/lib/Drupal/node/Tests/NodeFieldMultilingualTestCase.php
--- b/core/modules/node/lib/Drupal/node/Tests/NodeFieldMultilingualTestCase.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeFieldMultilingualTestCase.php
@@ -133,7 +133,7 @@
     // Check if node body is showed.
     $this->drupalGet('node/' . $node->id());
      $body = $this->xpath('//article[contains(concat(" ", normalize-space(@class), " "), :node-class)]//div[@class=:content-class]/descendant::p', array(
-      ':node-class' => 'node ',
+      ':node-class' => ' node ',
       ':content-class' => 'node__content',
     ));
     $this->assertEqual(current($body), $node->body->value, 'Node body found.');
diff -u b/core/modules/node/lib/Drupal/node/Tests/NodePostSettingsTest.php b/core/modules/node/lib/Drupal/node/Tests/NodePostSettingsTest.php
--- b/core/modules/node/lib/Drupal/node/Tests/NodePostSettingsTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodePostSettingsTest.php
@@ -45,7 +45,7 @@
 
     // Check that the post information is displayed.
     $node = $this->drupalGetNodeByTitle($edit['title[0][value]']);
-    $elements = $this->xpath('//*[contains(@class,:class)]', array(':class' => 'node__meta'));
+    $elements = $this->xpath('//*[contains(@class, :class)]', array(':class' => 'node__meta'));
     $this->assertEqual(count($elements), 1, 'Post information is displayed.');
     $node->delete();
 
diff -u b/core/modules/node/lib/Drupal/node/Tests/NodeTitleTest.php b/core/modules/node/lib/Drupal/node/Tests/NodeTitleTest.php
--- b/core/modules/node/lib/Drupal/node/Tests/NodeTitleTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeTitleTest.php
@@ -61,7 +61,7 @@
     $this->assertEqual(current($this->xpath($xpath)), $node->label(), 'Node breadcrumb is equal to node title.', 'Node');
 
     // Test node title in comment preview.
-    $this->assertEqual(current($this->xpath('//article[contains(concat(" ", normalize-space(@class), " "), :node-class)]/h2/a/span', array(':node-class' => 'node--type-' . $node->bundle() . ' '))), $node->label(), 'Node preview title is equal to node title.', 'Node');
+    $this->assertEqual(current($this->xpath('//article[contains(concat(" ", normalize-space(@class), " "), :node-class)]/h2/a/span', array(':node-class' => ' node--type-' . $node->bundle() . ' '))), $node->label(), 'Node preview title is equal to node title.', 'Node');
 
     // Test node title is clickable on teaser list (/node).
     $this->drupalGet('node');
diff -u b/core/modules/node/templates/node.html.twig b/core/modules/node/templates/node.html.twig
--- b/core/modules/node/templates/node.html.twig
+++ b/core/modules/node/templates/node.html.twig
@@ -5,11 +5,11 @@
  *
  * Available variables:
  * - node: Full node entity.
- *   - node.id: The node ID
+ *   - node.id: The node ID.
  *   - node.bundle: The type of the node, for example, "page" or "article".
  *   - node.authorid: The user ID of the node author.
- *   - node.createdtime: Formatted creation date. Preprocess functions can reformat
- *     it by calling format_date() with the desired parameters on
+ *   - node.createdtime: Formatted creation date. Preprocess functions can
+ *     reformat it by calling format_date() with the desired parameters on
  *     $variables['node']->getCreatedTime().
  *   - node.promoted: Whether the node is promoted to the front page.
  *   - node.sticky: Whether the node is 'sticky'. Sticky nodes are ordered above
@@ -37,15 +37,16 @@
  *   - node--[type]: The current node type. For example, if the node is a
  *     "Article" it would result in "node--article". Note that the machine
  *     name will often be in a short form of the human readable label.
- *   - node--view-mode-[view_mode]: The View Mode of the node; for example, a teaser
- *     would result in: "node--view-mode-teaser", and
+ *   - node--view-mode-[view_mode]: The View Mode of the node; for example, a
+ *     teaser would result in: "node--view-mode-teaser", and
  *     full: "node--view-mode-full".
  *   - node--preview: Whether a node is in preview mode.
  *   The following are controlled through the node publishing options.
  *   - node--promoted: Appears on nodes promoted to the front page.
- *   - node---sticky: Appears on nodes ordered above other non-sticky nodes in teaser
- *     listings.
- *   - node---unpublished: Appears on unpublished nodes visible only to site admins.
+ *   - node---sticky: Appears on nodes ordered above other non-sticky nodes in
+ *     teaser listings.
+ *   - node---unpublished: Appears on unpublished nodes visible only to site
+ *     admins.
  * - title_prefix: Additional output populated by modules, intended to be
  *   displayed in front of the main title tag that appears in the template.
  * - title_suffix: Additional output populated by modules, intended to be
@@ -77,7 +78,7 @@
  * @ingroup themeable
  */
 #}
-<article {{ attributes }}>
+<article{{ attributes }}>
 
   {{ title_prefix }}
   {% if not page %}
@@ -94,7 +95,7 @@
     </footer>
   {% endif %}
 
-  <div class="node__content {{ content_attributes.class }}"{{ content_attributes|without('class') }}>
+  <div class="node__content{{ content_attributes.class }}"{{ content_attributes|without('class') }}>
     {{ content|without('links') }}
   </div>
 
diff -u b/core/themes/bartik/templates/node.html.twig b/core/themes/bartik/templates/node.html.twig
--- b/core/themes/bartik/templates/node.html.twig
+++ b/core/themes/bartik/templates/node.html.twig
@@ -5,11 +5,11 @@
  *
  * Available variables:
  * - node: Full node entity.
- *   - node.id: The node ID
+ *   - node.id: The node ID.
  *   - node.bundle: The type of the node, for example, "page" or "article".
  *   - node.authorid: The user ID of the node author.
- *   - node.createdtime: Formatted creation date. Preprocess functions can reformat
-       it by calling format_date() with the desired parameters on
+ *   - node.createdtime: Formatted creation date. Preprocess functions can
+ *     reformat it by calling format_date() with the desired parameters on
  *     $variables['node']->getCreatedTime().
  *   - node.promoted: Whether the node is promoted to the front page.
  *   - node.sticky: Whether the node is 'sticky'. Sticky nodes are ordered above
@@ -36,15 +36,16 @@
  *   - node--[type]: The current node type. For example, if the node is a
  *     "Article" it would result in "node--article". Note that the machine
  *     name will often be in a short form of the human readable label.
- *   - node--view-mode-[view_mode]: The View Mode of the node; for example, a teaser
- *     would result in: "node--view-mode-teaser", and
- *     full: "node--view-mode-full".
+ *   - node--view-mode-[view_mode]: The View Mode of the node; for example, a
+ *     teaser would result in: "node--view-mode-teaser",
+ *     and full: "node--view-mode-full".
  *   - is-preview: Whether a node is in preview mode.
  *   The following are controlled through the node publishing options.
  *   - node--promoted: Appears on nodes promoted to the front page.
- *   - node--sticky: Appears on nodes ordered above other non-sticky nodes in teaser
- *     listings.
- *   - node--unpublished: Appears on unpublished nodes visible only to site admins.
+ *   - node--sticky: Appears on nodes ordered above other non-sticky nodes in
+ *     teaser listings.
+ *   - node--unpublished: Appears on unpublished nodes visible only to site
+ *     admins.
  * - title_prefix: Additional output populated by modules, intended to be
  *   displayed in front of the main title tag that appears in the template.
  * - title_suffix: Additional output populated by modules, intended to be