How to disable GTK+ 3.12 client side decorations?
Solution 1:
You could try gtk3-nocsd: article on WebUpd8
sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt-get update
sudo apt-get install gtk3-nocsd
Add the following to your "~/.profile"
export GTK_CSD=0
export LD_PRELOAD=/path/to/gtk3-nocsd.so
The author an WebUpd8 writes, that Unity doesn't start with that, so you can edit a .desktop file in /usr/share/applications, for example gthumb:
/usr/share/applications/gthumb.desktop
Add the follwing to "Exec=":
env LD_PRELOAD=/usr/lib/gtk3-nocsd/gtk3-nocsd.so
so that it looks like this:
Exec=env LD_PRELOAD=/usr/lib/gtk3-nocsd/gtk3-nocsd.so gthumb %U