Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0
I don't know anything about macs, and not sure if I have this right
for Linux. But I think locale should be referring to a non-computer
language.
On my Linux machine,
#localectl
System Locale: LANG=en_US.UTF-8
VC Keymap: us
X11 Layout: us
I can set the above locale with
#localectl set-locale LANG=en_US.UTF-8
I can list all locales with
#localectl list-locales
#man localectl
will give more info.
I'm guessing that on the mac you will probably have some other
commands to deal with this, but this may help some linux user.
Fred