I realized that the reason dates etc. looked odd in various
applications was that my locale was "wrong"....

I was using "en_US.UTF-8" instead of "en_GB.UTF-8"

How to set locale in FreeBSD? 

I found a guide at [0]

And since there's only one user of my laptop I don't need to worry
about setting the locale "globally" so I did:

Edit /etc/login.conf to change settings to:

  :charset=UTF-8:\
  :lang=en_GB.UTF-8:

ran "cap_mkdb":

doas cap_mkdb /etc/login.conf

edited /etc/profile to add the environment variables 

export LANG=en_GB.UTF-8
export LC_ALL=en_GB.UTF-8


each user will get these on login...

Logged out...


Logged in....

Checked a previously "wrong" date format displayed in Librewolf, on
my Murena cloud calendar.... and now the date is shown as
dd/mm/yyyy as it should be. 

Another FreeBSD configuration job done, simply and without fuss.




[0]https://www.siberoloji.com/how-to-configure-locale-settings-on-freebsd-operating-system/