Comment 5 for bug 986988

It helps for a UI freeze exception that this is the non-default session for Edubuntu (Unity is default for 12.04) and there is no official documentation for the GNOME Classic session.

If anyone would like to test the fix for this & the GTK tweak out, it's relatively simple.

Add gtk-icon-sizes = panel-menu-bar=24,24 to /etc/gtk-3.0/settings.ini

And for /usr/share/themes/Ambiance/gtk-3.0/apps/gnome-panel.css
add
-PanelMenuBar-icon-visible: true;
on a new line right below
PanelMenuBar.menubar.menuitem {

Then restart gnome-panel or log out and back in. I would have proposed this a lot sooner if I had known this was possible.