Locale failure when switching LC_TIME

I installed xfce nixos recently and am making minor changes. I set il8n LC_TIME to en_CA in order to get yyyy-mm-dd date format as I am Canadian. Not sure if was related but my libreoffice files were showing square boxes instead of letters so I switched LC… back to en_US. I’m ignoring this problem for a while and just dealing with locale. I got the following warning that may be of interest to some. erl: warning: Setting locale failed. perl: warning: Please check that your locale settings: L...