Andreas' workaround of:
sudo cp /usr/share/themes/Human/gtk-2.0/gtkrc /usr/share/themes/Human/gtk-2.0/gtkrc.en
...seems to work far better than my gdmlogin workaround.
I'm guessing this is a spelling mistake somewhere - missing .en off the end of /usr/share/themes/Human/gtk-2.0/gtkrc.en
Andreas' workaround of:
sudo cp /usr/share/ themes/ Human/gtk- 2.0/gtkrc /usr/share/ themes/ Human/gtk- 2.0/gtkrc. en
...seems to work far better than my gdmlogin workaround.
I'm guessing this is a spelling mistake somewhere - missing .en off the end of /usr/share/ themes/ Human/gtk- 2.0/gtkrc. en