--- a/devtools/client/preferences/debugger.js
+++ b/devtools/client/preferences/debugger.js
@@ -1,16 +1,12 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
-#ifdef RELEASE_OR_BETA
-pref("devtools.debugger.new-debugger-frontend", false);
-#else
 pref("devtools.debugger.new-debugger-frontend", true);
-#endif
 
 // Enable the Debugger
 pref("devtools.debugger.enabled", true);
 pref("devtools.debugger.chrome-debugging-host", "localhost");
 pref("devtools.debugger.chrome-debugging-port", 6080);
 pref("devtools.debugger.chrome-debugging-websocket", false);
 pref("devtools.debugger.remote-host", "localhost");
 pref("devtools.debugger.remote-timeout", 20000);

--- a/devtools/client/preferences/moz.build
+++ b/devtools/client/preferences/moz.build
@@ -1,10 +1,13 @@
 # -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
 # vim: set filetype=python:
 # 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/.
 
 JS_PREFERENCE_PP_FILES += [
-    'debugger.js',
     'devtools.js'
 ]
+
+JS_PREFERENCE_FILES += [
+    'debugger.js',
+]