diff --git a/toolkit/xre/nsNativeAppSupportWin.cpp b/toolkit/xre/nsNativeAppSupportWin.cpp
index b7832cdc0c1..cdd8735c563 100644
--- a/toolkit/xre/nsNativeAppSupportWin.cpp
+++ b/toolkit/xre/nsNativeAppSupportWin.cpp
@@ -336,15 +336,16 @@ nsNativeAppSupportWin::CheckConsole() {
     // It will succeed when the parent process is a command line,
     // so that stdio will be displayed in it.
     if (AttachConsole(ATTACH_PARENT_PROCESS)) {
-        // Change std handles to refer to new console handles.
-        // Before doing so, ensure that stdout/stderr haven't been redirected to a valid file
+        // Change std handles to refer to new console handles. Before doing so,
+        // ensure that stdout/stderr haven't been redirected to a valid file
         if (_fileno(stdout) == -1 || _get_osfhandle(fileno(stdout)) == -1)
             freopen("CONOUT$", "w", stdout);
+        // There isn't any `CONERR$`, so that we merge stderr into CONOUT$
+        // http://msdn.microsoft.com/en-us/library/windows/desktop/ms683231%28v=vs.85%29.aspx
         if (_fileno(stderr) == -1 || _get_osfhandle(fileno(stderr)) == -1)
-            freopen("CONERR$", "w", stderr);
+            freopen("CONOUT$", "w", stderr);
         if (_fileno(stdin) == -1 || _get_osfhandle(fileno(stdin)) == -1)
             freopen("CONIN$", "r", stdin);
-        return;
     }
 
     for ( int i = 1; i < gArgc; i++ ) {