I recently upgrade my UBUNTU machine to version 10.04 and I hit in to a small problem: when you set the panel to be transparent in the default Ambiance theme in Ubuntu 10.04, you will find that some panel items’ backgrounds are not transparent.
You can make them transparent and consistent with others, following these steps:
cp -R /usr/share/themes/Ambiance ~/.themes/
Edit ~/.themes/Ambiance/gtk-2.0/gtkrc and comment out the line bg_pixmap[NORMAL] = “panel_bg.png” placing a # at the beginning of the line like this:
# bg_pixmap[NORMAL] = "panel_bg.png"
Go to System > Preferences > Appearance, switch to the other theme and then back to the Ambiance theme.
Note: If you’d like to change the Radiance theme, replace Ambiance with Radiance in the above command lines. If you like to change the New Wave theme, then enter cp -R /usr/share/themes/”New Wave” ~/.themes/ and edit ~/.themes/”New Wave”/gtk-2.0/gtkrc , search for and comment out this line bg_pixmap[NORMAL] = “Images/Panel/PanelBarLong.png”.