Don't know what's happening here. First, I love Devuan. It's quick and
efficient.

    I use Thunderbird for my mail and calendar needs.  I went to
    schedule an appointment with my doctor, and was surprised to find,
    for the first time, the time display in 24-hour format. Never
    happens with any other distro.  Any idea how I can change this to
    12-hour AM/PM format?  Thanks.