Gnome-terminal window borders

[Colin Law]

I have a problem using gnome-terminal in Ubuntu 16.10 (Unity), in that
the windows do not have a obvious border and when one gets overlapped
terminal windows it becomes very confusing as to which text is in
which window.  On previous versions of ubuntu this could be changed by
adding the line below to
/usr/share/themes/Ambiance/gtk-3.0/apps/gnome-terminal.css

UnityDecoration { -UnityDecoration-extents: 28px 1px 1px 1px; }

Unfortunately this no longer seems to have the desired effect (or any
noticeable effect at all as far as I can see).  Can anyone suggest
what I can do to add a border to the windows?

Colin