http://askubuntu.com/questions/34214/how-do-i-disable-overlay-scrollbars

假干：

In 12.04 LTS there's a . Just run

gsettings set org.gnome.desktop.interface ubuntu-overlay-scrollbars false

in a terminal. Apps opened afterwards will have the non-ayatana scrollbar.

To get the default behavior back, run

gsettings reset org.gnome.desktop.interface ubuntu-overlay-scrollbars

If you are using 12.10 or later, run

gsettings set com.canonical.desktop.interface scrollbar-mode normal

And to return to the default, run

gsettings reset com.canonical.desktop.interface scrollbar-mode

真干：

You can remove the scrollbars completely by typing

sudo apt-get remove overlay-scrollbar liboverlay-scrollbar