Just got a fresh install of Ubuntu 18.04. Can't use Powerline/Nerd Fonts in gnome-terminal. They don't show up in the list of fonts.(However the fonts are installed, and they show up in the menus for Firefox and Tilix).
I've refreshed the font cache, and also tried to change the permissions of the font(chmod-ing it). No use. Used to work just fine on 17.10. This broke after upgrading to 18.04