all window manager shortcuts (e.g. Alt-F4) broken in Unity

[Stefan Majewsky]

Since about a week, all window manager shortcuts are broken, that is: pressing them does nothing. This affects most prominently Alt-F4 and Alt-Tab. The panel's shortcuts, like Alt, Super and Super+Number, are still working, as are shortcuts inside applications (and every other keyboard input).

xev tells me that all input events for Alt-F4 are sent to the client window.

This system is a virtual machine in VirtualBox under a 64-bit Windows 7 host; guest additions are installed. The system is used for web development; my typical session contains Firefox, Konsole (from KDE), Pidgin and pgAdmin III.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: metacity 1:2.34.1-1ubuntu11
ProcVersionSignature: Ubuntu 3.2.0-27.43-generic 3.2.21
Uname: Linux 3.2.0-27-generic x86_64
ApportVersion: 2.0.1-0ubuntu11
Architecture: amd64
Date: Mon Aug 6 08:59:53 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
ProcEnviron:
 LANGUAGE=
 TERM=xterm-256color
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/zsh
SourcePackage: metacity
UpgradeStatus: Upgraded to precise on 2012-06-05 (61 days ago)