grid plugin activate without any reason

[eric]

Start a session
open firefox
click on the workspace selector
click once again on the worspace selector
click on the workspace with firefox
put your mouse on the left as if you wanted to open an app.

The grid plugin activates with the orange colour for no reason and without any window.

see the video attached

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: unity 6.4.0-0ubuntu6
ProcVersionSignature: Ubuntu 3.5.0-15.22-generic 3.5.4
Uname: Linux 3.5.0-15-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] est un dossier: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 304.43 Sun Aug 19 20:14:03 PDT 2012
 GCC version: gcc version 4.7.1 (Ubuntu/Linaro 4.7.1-9ubuntu2)
ApportVersion: 2.5.2-0ubuntu4
Architecture: amd64
CompizPlugins: [core,composite,opengl,decor,compiztoolbox,move,gnomecompat,snap,mousepoll,obs,imgpng,resize,grid,regex,vpswitch,place,wall,session,unitymtgrabhandles,animation,workarounds,fade,expo,scale,ezoom,unityshell]
Date: Thu Sep 20 16:40:22 2012
DistUpgraded: Fresh install
DistroCodename: quantal
DistroVariant: ubuntu
DkmsStatus: nvidia-current, 304.43, 3.5.0-15-generic, x86_64: installed
GraphicsCard:
 NVIDIA Corporation G94 [GeForce 9600 GT] [10de:0622] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Giga-byte Technology GV-NX96T512HP [1458:3481]
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
JockeyStatus:
 kmod:nvidia_experimental_304 - Experimental NVIDIA binary Xorg driver, kernel module and VDPAU library (Free, Disabled, Not in use)
 kmod:nvidia_173 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
 kmod:nvidia_current - nvidia_current (Proprietary, Enabled, Not in use)
 kmod:nvidia_173_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
 kmod:nvidia_current_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
MachineType: System manufacturer P5Q DELUXE
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-15-generic root=UUID=6b0fa1e9-07f9-4e33-992d-d8b54f4e506b ro quiet splash
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)
XorgConf:
 Section "Device"
  Identifier "Default Device"
  Option "NoLogo" "True"
 EndSection
dmi.bios.date: 07/10/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2301
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: P5Q DELUXE
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2301:bd07/10/2009:svnSystemmanufacturer:pnP5QDELUXE:pvrSystemVersion:rvnASUSTeKComputerINC.:rnP5QDELUXE:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.name: P5Q DELUXE
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer
version.compiz: compiz 1:0.9.8.0-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.39-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0~git20120917.7cfd42ce-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0~git20120917.7cfd42ce-0ubuntu3
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.13.0-0ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.99.99~git20120713.6ef1ad6a-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.20.8-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.2-0ubuntu1

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1037142, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.