I have taken a look at Gtk Theme change menu bar hover color but it doesn't seem to work on 12.04, nor can I find those lines in 12.04. My menus look like the below when hovered over for some applications such as Eclipse, Pidgin, LibreOffice etc. Where as it looks much better on Nautilus and a few others. How to change the text colour on hover to white? Edit: I use Cinnamon with Ambiance theme