--- a/b2g/chrome/content/shell.js
+++ b/b2g/chrome/content/shell.js
@@ -482,17 +482,17 @@ function startDebugger() {
   if (!DebuggerServer.initialized) {
     // Allow remote connections.
     DebuggerServer.init(function () { return true; });
     DebuggerServer.addActors('chrome://browser/content/dbg-browser-actors.js');
   }
 
   let port = Services.prefs.getIntPref('devtools.debugger.remote-port') || 6000;
   try {
-    DebuggerServer.openListener(port, false);
+    DebuggerServer.openListener(port);
   } catch (e) {
     dump('Unable to start debugger server: ' + e + '\n');
   }
 }
 
 window.addEventListener('ContentStart', function(evt) {
   if (Services.prefs.getBoolPref('devtools.debugger.remote-enabled')) {
     startDebugger();

--- a/browser/devtools/debugger/DebuggerUI.jsm
+++ b/browser/devtools/debugger/DebuggerUI.jsm
@@ -437,17 +437,17 @@ ChromeDebuggerProcess.prototype = {
    * Initializes the debugger server.
    */
   _initServer: function RDP__initServer() {
     if (!DebuggerServer.initialized) {
       DebuggerServer.init(this._allowConnection);
       DebuggerServer.addBrowserActors();
     }
     DebuggerServer.closeListener();
-    DebuggerServer.openListener(DebuggerPreferences.remotePort, false);
+    DebuggerServer.openListener(DebuggerPreferences.remotePort);
   },
 
   /**
    * Prompt the user to accept or decline the incoming connection.
    *
    * @return true if the connection should be permitted, false otherwise
    */
   _allowConnection: function RDP__allowConnection() {

--- a/mobile/android/chrome/content/browser.js
+++ b/mobile/android/chrome/content/browser.js
@@ -5669,17 +5669,17 @@ var RemoteDebugger = {
   _start: function rd_start() {
     try {
       if (!DebuggerServer.initialized) {
         DebuggerServer.init(this._allowConnection);
         DebuggerServer.addActors("chrome://browser/content/dbg-browser-actors.js");
       }
 
       let port = this._getPort();
-      DebuggerServer.openListener(port, false);
+      DebuggerServer.openListener(port);
       dump("Remote debugger listening on port " + port);
     } catch(e) {
       dump("Remote debugger didn't start: " + e);
     }
   },
 
   _stop: function rd_start() {
     DebuggerServer.closeListener();

--- a/modules/libpref/src/init/all.js
+++ b/modules/libpref/src/init/all.js
@@ -315,16 +315,18 @@ pref("toolkit.telemetry.infoURL", "http:
 // i.e. dynamically constructed SQL strings or SQL executed by addons against addon DBs
 pref("toolkit.telemetry.debugSlowSql", false);
 
 // Disable remote debugging protocol logging
 pref("devtools.debugger.log", false);
 // Disable remote debugging connections
 pref("devtools.debugger.remote-enabled", false);
 pref("devtools.debugger.remote-port", 6000);
+// Force debugger server binding on the loopback interface
+pref("devtools.debugger.force-local", true);
 
 // view source
 pref("view_source.syntax_highlight", true);
 pref("view_source.wrap_long_lines", false);
 pref("view_source.editor.external", false);
 pref("view_source.editor.path", "");
 // allows to add further arguments to the editor; use the %LINE% placeholder
 // for jumping to a specific line (e.g. "/line:%LINE%" or "--goto %LINE%")

--- a/testing/marionette/components/marionettecomponent.js
+++ b/testing/marionette/components/marionettecomponent.js
@@ -70,17 +70,17 @@ MarionetteComponent.prototype = {
       try {
         Cu.import('resource:///modules/devtools/dbg-server.jsm');
         DebuggerServer.addActors('chrome://marionette/content/marionette-actors.js');
         // This pref is required for the remote debugger to open a socket,
         // so force it to true.  See bug 761252.
         Services.prefs.setBoolPref('devtools.debugger.remote-enabled', true);
         // Always allow remote connections.
         DebuggerServer.initTransport(function () { return true; });
-        DebuggerServer.openListener(port, true);
+        DebuggerServer.openListener(port);
       }
       catch(e) {
         this.logger.error('exception: ' + e.name + ', ' + e.message);
       }
     }
   },
 
   uninit: function mc_uninit() {

--- a/toolkit/devtools/debugger/server/dbg-server.js
+++ b/toolkit/devtools/debugger/server/dbg-server.js
@@ -118,31 +118,35 @@ var DebuggerServer = {
     this.addActors("chrome://global/content/devtools/dbg-browser-actors.js");
   },
 
   /**
    * Listens on the given port for remote debugger connections.
    *
    * @param aPort int
    *        The port to listen on.
-   * @param aLocalOnly bool
-   *        If true, server will listen on the loopback device.
    */
-  openListener: function DH_openListener(aPort, aLocalOnly) {
+  openListener: function DH_openListener(aPort) {
     if (!Services.prefs.getBoolPref("devtools.debugger.remote-enabled")) {
       return false;
     }
     this._checkInit();
 
     if (this._listener) {
       throw "Debugging listener already open.";
     }
 
+    let localOnly = false;
+    // A preference setting can force binding on the loopback interface.
+    if (Services.prefs.getBoolPref("devtools.debugger.force-local")) {
+      localOnly = true;
+    }
+
     try {
-      let socket = new ServerSocket(aPort, aLocalOnly, 4);
+      let socket = new ServerSocket(aPort, localOnly, 4);
       socket.asyncListen(this);
       this._listener = socket;
     } catch (e) {
       dumpn("Could not start debugging listener on port " + aPort + ": " + e);
       throw Cr.NS_ERROR_NOT_AVAILABLE;
     }
 
     return true;

--- a/toolkit/devtools/debugger/tests/unit/test_dbgglobal.js
+++ b/toolkit/devtools/debugger/tests/unit/test_dbgglobal.js
@@ -4,36 +4,36 @@
 Cu.import("resource:///modules/devtools/dbg-server.jsm");
 Cu.import("resource:///modules/devtools/dbg-client.jsm");
 
 function run_test()
 {
   // Should get an exception if we try to interact with DebuggerServer
   // before we initialize it...
   check_except(function() {
-    DebuggerServer.openListener(2929, true);
+    DebuggerServer.openListener(2929);
   });
   check_except(DebuggerServer.closeListener);
   check_except(DebuggerServer.connectPipe);
 
   // Allow incoming connections.
   DebuggerServer.init(function () { return true; });
 
   // These should still fail because we haven't added a createRootActor
   // implementation yet.
   check_except(function() {
-    DebuggerServer.openListener(2929, true);
+    DebuggerServer.openListener(2929);
   });
   check_except(DebuggerServer.closeListener);
   check_except(DebuggerServer.connectPipe);
 
   DebuggerServer.addActors("resource://test/testactors.js");
 
   // Now they should work.
-  DebuggerServer.openListener(2929, true);
+  DebuggerServer.openListener(2929);
   DebuggerServer.closeListener();
 
   // Make sure we got the test's root actor all set up.
   let client1 = DebuggerServer.connectPipe();
   client1.hooks = {
     onPacket: function(aPacket1) {
       do_check_eq(aPacket1.from, "root");
       do_check_eq(aPacket1.applicationType, "xpcshell-tests");

--- a/toolkit/devtools/debugger/tests/unit/test_dbgsocket.js
+++ b/toolkit/devtools/debugger/tests/unit/test_dbgsocket.js
@@ -22,17 +22,17 @@ function really_long() {
   for (let i = 0; i < 18; i++) {
     ret += ret;
   }
   return ret;
 }
 
 function test_socket_conn()
 {
-  DebuggerServer.openListener(2929, true);
+  DebuggerServer.openListener(2929);
 
   let unicodeString = "(╯°□°）╯︵ ┻━┻";
   let transport = debuggerSocketConnect("127.0.0.1", 2929);
   transport.hooks = {
     onPacket: function(aPacket) {
       this.onPacket = function(aPacket) {
         do_check_eq(aPacket.unicode, unicodeString);
         transport.close();