https://znil.net/index.php?title=Ubuntu_18.04.x_LTS_-_Guacamole_HTML5_Remotedesktop_Gateway_installieren_mit_Apache_Reverse_Proxy
echo xfce4-session> ~/.xsession
apt-get install letsencrypt
apt-get install python-certbot-apache
with the "certonly" option. To non-interactively renew *all* of
your certificates, run "certbot renew"
