diff --git a/xpfe/components/sample/public/nsISampleAppShellComponent.idl b/xpfe/components/sample/public/nsISampleAppShellComponent.idl
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+#include "nsIAppShellComponent.idl"
+
+/*------------------------ nsISampleAppShellComponent --------------------------
+| This file describes the interface for a sample "application shell            |
+| component."                                                                  |
+|                                                                              |
+| The sample component demonstrates most of what you need to know to           |
+| implement your own appshell components.  In addition, it provides some       |
+| facilities for testing XUL dialogs.                                          |
+|                                                                              |
+| You don't need to put those in your component!                               |
+------------------------------------------------------------------------------*/
+[scriptable, uuid(a6cf90fe-15b3-11d2-932e-00805f8add32)]
+interface nsISampleAppShellComponent : nsIAppShellComponent {
+
+    /*---------------------------- DoDialogTests -------------------------------
+    | Displays a dialog from which you can click buttons to perform these      |
+    | dialogs tests:                                                           |
+    |   o Non-modal dialog from C++                                            |
+    |   o Non-modal dialog from JavaScript                                     |
+    |   o Modal dialog from C++                                                |
+    |   o Modal dialog from JavaScript                                         |
+    --------------------------------------------------------------------------*/
+    void DoDialogTests();
+};
+
+%{C++
+#define NS_ISAMPLEAPPSHELLCOMPONENT_PROGID NS_IAPPSHELLCOMPONENT_PROGID "/sample"
+#define NS_ISAMPLEAPPSHELLCOMPONENT_CLASSNAME "Mozilla Sample App Shell Component"
+#define NS_DECL_ISAMPLEAPPSHELLCOMPONENT \
+    NS_IMETHOD DoDialogTests();
+%}