diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 4230087..3efb271 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -1671,26 +1671,6 @@ function template_preprocess_table(&$variables) {
 }
 
 /**
- * Returns HTML for a marker for new or updated content.
- *
- * @param $variables
- *   An associative array containing:
- *   - type: Number representing the marker type to display. See MARK_NEW,
- *     MARK_UPDATED, MARK_READ.
- */
-function theme_mark($variables) {
-  $type = $variables['status'];
-  if (\Drupal::currentUser()->isAuthenticated()) {
-    if ($type == MARK_NEW) {
-      return ' <span class="marker">' . t('new') . '</span>';
-    }
-    elseif ($type == MARK_UPDATED) {
-      return ' <span class="marker">' . t('updated') . '</span>';
-    }
-  }
-}
-
-/**
  * Prepares variables for item list templates.
  *
  * Default template: item-list.html.twig.
@@ -2562,6 +2542,7 @@ function drupal_common_theme() {
     ),
     'mark' => array(
       'variables' => array('status' => MARK_NEW),
+      'template' => 'mark',
     ),
     'item_list' => array(
       'variables' => array('items' => array(), 'title' => '', 'list_type' => 'ul', 'attributes' => array(), 'empty' => NULL),
diff --git a/core/modules/system/templates/mark.html.twig b/core/modules/system/templates/mark.html.twig
new file mode 100644
index 0000000..2798bb0
--- /dev/null
+++ b/core/modules/system/templates/mark.html.twig
@@ -0,0 +1,22 @@
+{#
+/**
+ * @file
+ * Default theme implementation for a marker for new or updated content.
+ *
+ * Available variables:
+ * - status: Number representing the marker status to display. Use the constants
+ *   below for comparison:
+ *   - MARK_NEW
+ *   - MARK_UPDATED
+ *   - MARK_READ
+ *
+ * @ingroup themeable
+ */
+#}
+{% if logged_in %}
+  {% if status is constant('MARK_NEW') %}
+    <span class="marker">{{ 'new'|t }}</span>
+  {% elseif status is constant('MARK_UPDATED') %}
+    <span class="marker">{{ 'updated'|t }}</span>
+  {% endif %}
+{% endif %}