Invisible butter bar should not be clickable.

chrome/browser/resources/file_manager/css/file_manager.css

 /* Copyright (c) 2012 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file. */
 
 html {
   height: 100%;
 }
 
 html.col-resize * {
   cursor: col-resize !important;
@@ skipping 102 matching lines @@
   width: 30%;
   z-index: 2;
 }
 
 body[new-ui] #butter-bar {
   color: #666;
   display: -webkit-box;
   padding: 15px;
 }
 
-#butter-bar:not(.visible) {
+body #butter-bar:not(.visible) {
   opacity: 0;
   pointer-events: none;
 }
 
 body[new-ui] #butter-bar:not(.visible) {
   display: none;
 }
 
 #butter-bar .content {
   -webkit-box-flex: 1.0;
@@ skipping 1904 matching lines @@
   background-image: -webkit-image-set(
     url('../images/files/ui/new-ui/button_list_view.png') 1x,
     url('../images/files/ui/new-ui/2x/button_list_view.png') 2x);
 }
 
 body[new-ui] menuitem#thumbnail-view {
   background-image: -webkit-image-set(
     url('../images/files/ui/new-ui/button_mosaic_view.png') 1x,
     url('../images/files/ui/new-ui/2x/button_mosaic_view.png') 2x);
 }