Which tab is currently selected in Terminator?
It depends on GTK3 You'll find what you are asking for here
You'll need to edit these for the active tab, in your file ~/.config/gtk-3.0/gtk.css
- for background :
.terminator-terminal-window notebook tab:checked - for font :
.terminator-terminal-window notebook tab:checked label
I think you will need to restart gnome-shell to force it to reload GTK css
ALT + F2 ; then run r
(correct me if I'm wrong)
This also figures in the Arch Wiki