Menu hotkey changes not reflected

Start gnome-terminal (version 3.6.2 in Trusty). Under Edit->Keyboard Shortcuts change one of the shortcuts that's shown in the menu (e.g. change Normal Size from Ctrl+0 to Ctrl+1).

Notice that the menu (gnome-terminal's View->Normal Size menu entry) still shows the old value, Ctrl+0. This hotkey no longer works, the new version is in effect. But you have to close the window and open a new gnome-terminal window for the menu to update.

The bug is specific to the Unity menu at the top of the desktop. If gnome-terminal is started with UBUNTU_MENUPROXY=0 (or under a different window manager), the shortcut in the menu is updated immediately.

gnome-terminal 3.12 got some heavy refactoring around its menu and hotkeys (https://bugzilla.gnome.org/show_bug.cgi?id=728121), yet, the same problem persists. So I really suspect it's a bug in Unity's app menu, rather than gnome-terminal.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: unity-gtk3-module 0.0.0+14.04.20140403-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-24.47-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.1
Architecture: amd64
CurrentDesktop: Unity
Date: Wed May 14 20:45:38 2014
InstallationDate: Installed on 2012-05-30 (714 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
SourcePackage: unity-gtk-module
UpgradeStatus: Upgraded to trusty on 2014-03-25 (50 days ago)