Update to Drupal 8.2.4. For more information, see https://www.drupal.org/project/drupal/releases/8.2.4

core/modules/outside_in/js/offcanvas.js

@@ -120,6 +120,9 @@
           of: window
         };
         settings.dialogClass = 'ui-dialog-offcanvas';
+        // Applies initial height to dialog based on window height.
+        // See http://api.jqueryui.com/dialog for all dialog options.
+        settings.height = $(window).height();
       }
     },
     'dialog:beforeclose': function (event, dialog, $element) {

core/modules/outside_in/js/outside_in.js

@@ -84,6 +84,17 @@
     event.preventDefault();
   }
 
+  /**
+   * Close any active toolbar tray before entering edit mode.
+   */
+  function closeToolbarTrays() {
+    $('#toolbar-bar')
+      .find('.toolbar-tab')
+      .not('.contextual-toolbar-tab')
+      .has('.toolbar-tray.is-active')
+      .find('.toolbar-item').click();
+  }
+
   /**
    *  Helper to switch edit mode state.
    *
@@ -97,10 +108,7 @@
     // Turn on edit mode.
     if (editMode) {
       $editButton.text(Drupal.t('Editing'));
-      // Close the Manage tray if open when entering edit mode.
-      if ($('#toolbar-item-administration-tray').hasClass('is-active')) {
-        $('#toolbar-item-administration').trigger('click');
-      }
+      closeToolbarTrays();
 
       $editables = $('[data-drupal-outsidein="editable"]').once('outsidein');
       if ($editables.length) {