diff --git a/core/modules/system/templates/region.html.twig b/core/modules/system/templates/region.html.twig
index c732984..fe566fe 100644
--- a/core/modules/system/templates/region.html.twig
+++ b/core/modules/system/templates/region.html.twig
@@ -5,9 +5,9 @@
  *
  * Available variables:
  * - content: The content for this region, typically blocks.
- * - attributes: HTML attributes.
- *   - attributes.class: Classes that can be used to style
- *     contextually through CSS.
+ * - attributes: HTML attributes for the region div, including:
+ *   - class: Classes that can be used to style contextually through CSS,
+ *     including:
  *     - region: The current template type (also know as "theming hook").
  *     - region-[name]: The name of the region with underscores replaced with
  *       dashes. For example, page_top region would have a region-page-top
@@ -22,7 +22,7 @@
  */
 #}
 {% if content %}
-  <div class="{{ attributes.class }}"{{ attributes }}>
+  <div{{ attributes }}>
     {{ content }}
   </div>
 {% endif %}