Issue #2831924 by tedbow, samuel.mortenson, drpal, Devin Carlson,...

Issue #2831924 by tedbow, samuel.mortenson, drpal, Devin Carlson, tim.plunkett, droplet: Outside In is intermittently unable to bind dialog events to the window

core/modules/outside_in/js/offcanvas.js

@@ -100,7 +100,17 @@
     }
   }
 
-  $(window).on({
+  /**
+   * Attaches off-canvas dialog behaviors.
+   *
+   * @type {Drupal~behavior}
+   *
+   * @prop {Drupal~behaviorAttach} attach
+   *   Attaches event listeners for off-canvas dialogs.
+   */
+  Drupal.behaviors.offCanvasEvents = {
+    attach: function () {
+      $(window).once('off-canvas').on({
         'dialog:aftercreate': function (event, dialog, $element, settings) {
           if ($element.is('#drupal-offcanvas')) {
             var eventData = {settings: settings, $element: $element};
@@ -137,11 +147,14 @@
         'dialog:beforeclose': function (event, dialog, $element) {
           if ($element.is('#drupal-offcanvas')) {
             $('body').removeClass('js-tray-open');
+            // Remove all *.offcanvas events
             $(document).off('.offcanvas');
             $(window).off('.offcanvas');
             $mainCanvasWrapper.css('padding-' + edge, 0);
           }
         }
       });
+    }
+  };
 
 })(jQuery, Drupal, Drupal.debounce, Drupal.displace);