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
@@ -8,12 +8,8 @@
  *   - id: The node ID.
  *   - bundle: The type of the node, for example, "page" or "article".
  *   - authorid: The user ID of the node author.
- *   - createdtime: Formatted creation date. Preprocess functions can reformat
- *     it by calling format_date() with the desired parameters on
- *     $variables['node']->getCreatedTime().
- *   - changedtime: Formatted changed date. Preprocess functions can reformat it
- *     by calling format_date() with the desired parameters on
- *     $variables['node']->getChangedTime().
+ *   - createdtime: Unix timestamps of creation date.
+ *   - changedtime: Unix timestamps of changed date.
  * - label: The title of the node.
  * - content: All node items. Use {{ content }} to print them all,
  *   or print a subset such as {{ content.field_example }}. Use
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
@@ -8,12 +8,8 @@
  *   - id: The node ID.
  *   - bundle: The type of the node, for example, "page" or "article".
  *   - authorid: The user ID of the node author.
- *   - createdtime: Formatted creation date. Preprocess functions can reformat
- *     it by calling format_date() with the desired parameters on
- *     $variables['node']->getCreatedTime().
- *   - changedtime: Formatted changed date. Preprocess functions can reformat it
- *     by calling format_date() with the desired parameters on
- *     $variables['node']->getChangedTime().
+ *   - createdtime: Unix timestamps of creation date.
+ *   - changedtime: Unix timestamps of changed date.
  * - label: The title of the node.
  * - content: All node items. Use {{ content }} to print them all,
  *   or print a subset such as {{ content.field_example }}. Use
only in patch2:
unchanged:
--- a/core/themes/classy/templates/content/node.html.twig
+++ b/core/themes/classy/templates/content/node.html.twig
@@ -8,9 +8,8 @@
  *   - id: The node ID.
  *   - bundle: The type of the node, for example, "page" or "article".
  *   - authorid: The user ID of the node author.
- *   - createdtime: Formatted creation date. Preprocess functions can
- *     reformat it by calling format_date() with the desired parameters on
- *     $variables['node']->getCreatedTime().
+ *   - createdtime: Unix timestamps of creation date.
+ *   - changedtime: Unix timestamps of changed date.
  * - label: The title of the node.
  * - content: All node items. Use {{ content }} to print them all,
  *   or print a subset such as {{ content.field_example }}. Use
xw