right click menu not working after viewing page source

Right click not working after viewing page source.

How to replicate:
* Go to any page
* Right click, choose 'View Page Source'
* Close source window
* Try to use the right click mouse button.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: firefox 13.0+build1-0ubuntu0.12.04.1
ProcVersionSignature: Ubuntu 3.2.0-24.39-generic-pae 3.2.16
Uname: Linux 3.2.0-24-generic-pae i686
AddonCompatCheckDisabled: False
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 2.0.1-0ubuntu8
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: rramiso 1807 F.... pulseaudio
BuildID: 20120601173917
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xefebc000 irq 43'
   Mixer name : 'SigmaTel STAC9200'
   Components : 'HDA:83847690,102801d4,00102201 HDA:14f12bfa,14f100c3,00090000'
   Controls : 14
   Simple ctrls : 7
Channel: release
Date: Sun Jun 10 21:24:26 2012
ForcedLayersAccel: False
IfupdownConfig:
 auto lo
 iface lo inet loopback
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423)
IpRoute:
 default via 192.168.11.1 dev wlan0 proto static
 169.254.0.0/16 dev wlan0 scope link metric 1000
 192.168.11.0/24 dev wlan0 proto kernel scope link src 192.168.11.8 metric 2
ProcEnviron:
 LANGUAGE=en_PH:en
 PATH=(custom, no user)
 LANG=en_PH.UTF-8
 SHELL=/bin/bash
Profiles:
 Profile0 - LastVersion=13.0/20120601173917
 Profile1 (Default) - LastVersion=13.0/20120601173917 (In use)
RelatedPackageVersions:
 rhythmbox-mozilla 2.96-0ubuntu4
 totem-mozilla 3.0.1-0ubuntu21
RunningIncompatibleAddons: False
SourcePackage: firefox
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/02/2007
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A05
dmi.board.name: 0NF743
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA05:bd04/02/2007:svnDellInc.:pnLatitudeD520:pvr:rvnDellInc.:rn0NF743:rvr:cvnDellInc.:ct8:cvr:
dmi.product.name: Latitude D520
dmi.sys.vendor: Dell Inc.