diff --git a/toolkit/devtools/server/actors/gcli.js b/toolkit/devtools/server/actors/gcli.js
index 9495c02d8823..91dea5bff35a 100644
--- a/toolkit/devtools/server/actors/gcli.js
+++ b/toolkit/devtools/server/actors/gcli.js
@@ -14,6 +14,8 @@ XPCOMUtils.defineLazyModuleGetter(this, "console",
                                   "resource://gre/modules/devtools/Console.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "CommandUtils",
                                   "resource:///modules/devtools/DeveloperToolbar.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Services",
+                                  "resource://gre/modules/Services.jsm");
 
 XPCOMUtils.defineLazyGetter(this, "require", function() {
   let { require } = Cu.import("resource://gre/modules/devtools/Require.jsm", {});
@@ -46,9 +48,7 @@ GcliActor.prototype.getCommandSpecs = function(request) {
 };
 
 GcliActor.prototype.execute = function(request) {
-  let windowMediator = Cc["@mozilla.org/appshell/window-mediator;1"]
-                        .getService(Ci.nsIWindowMediator);
-  let chromeWindow = windowMediator.getMostRecentWindow("navigator:browser");
+  let chromeWindow = Services.wm.getMostRecentWindow(DebuggerServer.chromeWindowType);
   let contentWindow = chromeWindow.gBrowser.selectedTab.linkedBrowser.contentWindow;
 
   let environment = CommandUtils.createEnvironment(chromeWindow.document,
diff --git a/toolkit/devtools/server/actors/root.js b/toolkit/devtools/server/actors/root.js
index f2114bafaef6..aa065f4ac761 100644
--- a/toolkit/devtools/server/actors/root.js
+++ b/toolkit/devtools/server/actors/root.js
@@ -8,6 +8,8 @@
 
 /* Root actor for the remote debugging protocol. */
 
+Cu.import("resource://gre/modules/Services.jsm");
+
 /**
  * Methods shared between RootActor and BrowserTabActor.
  */
@@ -330,7 +332,7 @@ RootActor.prototype = {
    */
   preNest: function() {
     // Disable events in all open windows.
-    let e = windowMediator.getEnumerator(null);
+    let e = Services.wm.getEnumerator(null);
     while (e.hasMoreElements()) {
       let win = e.getNext();
       let windowUtils = win.QueryInterface(Ci.nsIInterfaceRequestor)
@@ -345,7 +347,7 @@ RootActor.prototype = {
    */
   postNest: function(aNestData) {
     // Enable events in all open windows.
-    let e = windowMediator.getEnumerator(null);
+    let e = Services.wm.getEnumerator(null);
     while (e.hasMoreElements()) {
       let win = e.getNext();
       let windowUtils = win.QueryInterface(Ci.nsIInterfaceRequestor)
diff --git a/toolkit/devtools/server/actors/webbrowser.js b/toolkit/devtools/server/actors/webbrowser.js
index aff628f86c96..a9aa8a56685a 100644
--- a/toolkit/devtools/server/actors/webbrowser.js
+++ b/toolkit/devtools/server/actors/webbrowser.js
@@ -7,6 +7,7 @@
 "use strict";
 
 let promise = Cu.import("resource://gre/modules/commonjs/sdk/core/promise.js", {}).Promise;
+XPCOMUtils.defineLazyModuleGetter(this, "Services", "resource://gre/modules/Services.jsm");
 
 /**
  * Browser-specific actors.
@@ -19,7 +20,7 @@ let promise = Cu.import("resource://gre/modules/commonjs/sdk/core/promise.js", {
  */
 function allAppShellDOMWindows(aWindowType)
 {
-  let e = windowMediator.getEnumerator(aWindowType);
+  let e = Services.wm.getEnumerator(aWindowType);
   while (e.hasMoreElements()) {
     yield e.getNext();
   }
@@ -66,9 +67,6 @@ function createRootActor(aConnection)
                        });
 }
 
-var windowMediator = Cc["@mozilla.org/appshell/window-mediator;1"]
-                     .getService(Ci.nsIWindowMediator);
-
 /**
  * A live list of BrowserTabActors representing the current browser tabs,
  * to be provided to the root actor to answer 'listTabs' requests.
@@ -196,7 +194,7 @@ BrowserTabList.prototype._getChildren = function(aWindow) {
 };
 
 BrowserTabList.prototype.getList = function() {
-  let topXULWindow = windowMediator.getMostRecentWindow(DebuggerServer.chromeWindowType);
+  let topXULWindow = Services.wm.getMostRecentWindow(DebuggerServer.chromeWindowType);
 
   // As a sanity check, make sure all the actors presently in our map get
   // picked up when we iterate over all windows' tabs.
@@ -370,7 +368,7 @@ BrowserTabList.prototype.handleEvent = makeInfallible(function(aEvent) {
 BrowserTabList.prototype._listenToMediatorIf = function(aShouldListen) {
   if (!aShouldListen !== !this._listeningToMediator) {
     let op = aShouldListen ? "addListener" : "removeListener";
-    windowMediator[op](this);
+    Services.wm[op](this);
     this._listeningToMediator = aShouldListen;
   }
 };