--- a/devtools/client/webide/modules/app-validator.js
+++ b/devtools/client/webide/modules/app-validator.js
@@ -1,15 +1,15 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
 var {Ci,Cu,CC} = require("chrome");
-const promise = require("devtools/shared/deprecated-sync-thenables");
+const promise = require("promise");
 
 const {FileUtils} = Cu.import("resource://gre/modules/FileUtils.jsm", {});
 const Services = require("Services");
 const {Task} = Cu.import("resource://gre/modules/Task.jsm", {});
 var XMLHttpRequest = CC("@mozilla.org/xmlextras/xmlhttprequest;1");
 var strings = Services.strings.createBundle("chrome://devtools/locale/app-manager.properties");
 
 function AppValidator({ type, location }) {