Issue #3468769 by lhridley: Add {{ attributes }} to all occurrences of off-canvas-page-wrapper.html.twig in Drupal Core to facilitate adding attributes with theme suggestions hook_off_canvas_page_wrapper()

Issue #3468769 by lhridley: Add {{ attributes }} to all occurrences of off-canvas-page-wrapper.html.twig in Drupal Core to facilitate adding attributes with theme suggestions hook_off_canvas_page_wrapper().

Closes #3468769

core/modules/system/templates/off-canvas-page-wrapper.html.twig

@@ -15,12 +15,13 @@
  *
  * Available variables:
  * - children: Contains the child elements of the page.
+ * - attributes: Add attributes with hook_preprocess_off_canvas_page_wrapper().
  *
  * @ingroup themeable
  */
 #}
 {% if children %}
-  <div class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas>
+  <div{{ attributes }} class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas>
     {{ children }}
   </div>
 {% endif %}