Comment 1 for bug 1163529

As this bug is recent and don't seems closed, I'm adding information here rather than opening a new, strictly identical one.
Especially considering the Launchpad suggestion system of current existing bugs.

Need a secondary Fix to commit visibly so, as problem don't seems resolved in my case:
=> see this screenshot: http://i.imgur.com/RISXP6b.jpg
Screenshoted just after clicking on it to preview.
The image previewed is this one: http://i.imgur.com/HZsXpCj.jpg (1600x1083)

Information:
Dual monitor:
(Secondary) Left: 1600x1200 (native resolution used)
(Main) Right: 1920x1200 (as native resolution, but 1280x720 mode used, for reasons long to explain here).
=> The right monitor is the one of the screenshot.

Here is the configuration used in my Xorg.conf (NVidia GTX 260 card, last stable version of the driver from nvidia.com used which is the 319.23), watch especially the "metamodes" line so:

<<<< For my main right screen @ 1920x1200 used as 1280x720 but 1220x680 effective in fact because of the overscan of my monitor (ViewPortOut is the new method that need to be used to manage overscan on NVidia cards since few times) >>>>
Section "Screen"
 Identifier "Screen0"
 Device "Device0"
 Monitor "Monitor0"
 DefaultDepth 24
 Option "TwinView" "1"
 Option "TwinViewXineramaInfoOrder" "DFP-1"
 Option "metamodes" "CRT: 1600x1200_60 +0+0, DFP: 1280x720_60 { ViewPortOut=1220x680+30+20 } +1600+240"
 SubSection "Display"
  Depth 24
 EndSubSection
EndSection

<<<< DRIVER USED (the proprietary one from NVidia so) >>>>
Section "Device"
 Identifier "Device0"
 Driver "nvidia"
 VendorName "NVIDIA Corporation"
 BoardName "GeForce GTX 260"
 Option "NoLogo" "True"
EndSection

General information:
OS: Ubuntu 12.04.2 LTS (with Cinnamon)
Birdie version: the last one available via the DAILY repository (by apt-get install) of few hours ago