Unity dash becomes very slow/laggy when opening certain webpages (Launchpad) in Firefox

Hello,

the problem I'm reporting here is actually a weird interaction between the Nvidia propritary driver, Firefox and Unity, so I'm not sure if I should have reported it against Firefox or Nvidia driver instead.

With the propritary Nvidia driver installed, the following happens:
- When I visit certain webpages in Firefox, scrolling through them/interacting with them becomes very slow and laggy. The most prominent example are all kinds of paged from launchpad.net, e.g. https://launchpad.net/ubuntu/+bugs, or a random bug report page. This problem exists as long as I can remember (5 years?!), regardless of the version of Firefox or Nvidia driver.
- In Oneiric, there is an additional interaction of this slowness/laginess with Unity: If one of those "slow" pages is opened in Firefox as currently selected tab (e.g. a bugreport) and I press 'Super' to reveal the dash and launcher, they take a rather long time to appear in contrast to the normal behaviour and the animation is also slow and laggy (if the dash has come up, it works fine and sleek as usual, so it's the process of the dash/launcher coming up that is slow).
- Interestingly I don't experience this slowness of dash/launcher if I reveal them via mouse (hovering to the left screen side and clicking the dash button).

The slowness of certain webpages only happens in Firefox (not in Chromium for example), and only if propritary Nvidia drivers are installed, with Nouveau drivers this "slow pages" phenomenon disappears in Firefox too.

The additonal problem with the Dash in Oneric may seem small, but it can be rather annoying when trying to write bug reports for example.
In Natty there is no such slowness when opening the dash via 'Super' and a "slow" web page is opened, so I reported it to Unity in hope that there may be an easy workaround.
But the best thing of course would be if this "slow pages" issue would be fixed in Firefox and/or the Nvidia driver (the latter is of course beyond control of anyone not working for Nvidia :-( ).

Kind regards,
Jan

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: unity 4.16.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-11.18-generic 3.0.4
Uname: Linux 3.0.0-11-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
Date: Wed Sep 21 11:30:43 2011
DistUpgraded: Fresh install
DistroCodename: oneiric
DistroVariant: ubuntu
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta amd64 (20110919)
MachineType: Gigabyte Technology Co., Ltd. P35-DS3
ProcEnviron:
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz root=/dev/sda6
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/10/2008
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F13
dmi.board.name: P35-DS3
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF13:bd07/10/2008:svnGigabyteTechnologyCo.,Ltd.:pnP35-DS3:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnP35-DS3:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: P35-DS3
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz 1:0.9.5.94+bzr2803-0ubuntu5
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.26-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3
version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1