perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = (unset), LC_ALL = (unset), LANG = "en_US.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C").
Adding the following to
/etc/environment fixed the problem for me on Debian and Ubuntu (of course, modify to match the locale you want to use):
LANGUAGE=en_US.UTF-8 LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8 LC_CTYPE=en_US.UTF-8