--- a/dom/apps/src/AppsUtils.jsm
+++ b/dom/apps/src/AppsUtils.jsm
@@ -240,17 +240,17 @@ this.AppsUtils = {
 /**
  * Helper object to access manifest information with locale support
  */
 this.ManifestHelper = function(aManifest, aOrigin) {
   this._origin = Services.io.newURI(aOrigin, null, null);
   this._manifest = aManifest;
   let chrome = Cc["@mozilla.org/chrome/chrome-registry;1"].getService(Ci.nsIXULChromeRegistry)
                                                           .QueryInterface(Ci.nsIToolkitChromeRegistry);
-  let locale = chrome.getSelectedLocale("browser").toLowerCase();
+  let locale = chrome.getSelectedLocale("global").toLowerCase();
   this._localeRoot = this._manifest;
 
   if (this._manifest.locales && this._manifest.locales[locale]) {
     this._localeRoot = this._manifest.locales[locale];
   }
   else if (this._manifest.locales) {
     // try with the language part of the locale ("en" for en-GB) only
     let lang = locale.split('-')[0];