Comment 2 for bug 1652451

Note: 1474927, 1578830, and 1652451 all seem to refer to the same issue. The
error code noted is documented here:

    https://wiki.gnome.org/Apps/Terminal/FAQ#Exit_status_8

This followed by a reboot or logging back in ought to resolve the issue:

    sudo localectl set-locale LANG=en_US.utf8

If you've done something invasive with locales, you might need to do something
more invasive to resolve the issue, as noted here:

    https://askubuntu.com/questions/608330/problem-with-gnome-terminal-on-gnome-3-12-2/651169#651169

Thanks to timeless on Freenode for the link to the exit status.