This should work for Debian Jessie as well as for Ubuntu Server 16.04 - please take note of the distribution-specific differences marked within the text.

It has been tested with Ubuntu Server 16.04, with the “regular” (non-nightly) Arctica repository. Everything else is still avaiting tests by volunteers like you.

# add the X2Go repo
add-apt-repository ppa:x2go/ppa # for Ubuntu

apt-key adv --recv-keys --keyserver keys.gnupg.net E1F958385BFE2B6E # for Debian
echo 'deb http://packages.x2go.org/debian jessie main' >>/etc/apt/sources.list.d/x2go.list # for Debian

# add the Arctica repo
wget -qO - http://packages.arctica-project.org/archive.key | sudo apt-key add -
echo "deb http://packages.arctica-project.org/ubuntu xenial main" >> /etc/apt/sources.list.d/arctica.list # for Ubuntu
echo "deb http://packages.arctica-project.org/debian jessie main" >> /etc/apt/sources.list.d/arctica.list # for Debian

# OR try the Arctica nightly repo
echo "deb http://packages.arctica-project.org/ubuntu-nightly xenial main" >> /etc/apt/sources.list.d/arctica.list # for Ubuntu Nightly
echo "deb http://packages.arctica-project.org/debian-nightly jessie main" >> /etc/apt/sources.list.d/arctica.list # for Debian Nightly

# update the package list before installing anything
apt-get update

# update the base system to the current package versions
# Download everything first, then upgrade, then dist-upgrade
apt-get dist-upgrade -d -y && \
apt-get upgrade -y && \
apt-get dist-upgrade -y

# Install X2Go packages, a minimal MATE Desktop, and Firefox as test application
apt-get install -y \
    x2goserver \
    x2goserver-xsession \
    x2gomatebindings \
    mate-core \
    mate-applets mate-menus \
    mate-notification-daemon \
    mate-screensaver \
    libcanberra-pulse \
    firefox

apt-get install -y ubuntu-mate-themes # for Ubuntu
apt-get install -y mate-themes # for Debian


# add a user
useradd -m -s /bin/bash <username>
passwd <username>

On the X2GoServer, edit /etc/x2go/x2goagent.options:

• Search for the String “xinerama”, and when you encounter a line like this one, make sure there's the plus sign in front of “xinerama”: X2GO_NXAGENT_DEFAULT_OPTIONS+=“ +xinerama”
• Search for the String “XFIXES”, and when you encounter a line like this one, make sure there's the plus sign in front of “extension”: X2GO_NXAGENT_DEFAULT_OPTIONS+=“ +extension XFIXES”

Also on the X2GoServer, verify that /usr/bin/x2goagent is a symlink pointing to /usr/bin/nxagent.

Next, disable XINERAMA in your X2GoClient's session profile(s).

Credits: Most of the content of the initial revision of this page stems from an E-Mail by Walid Moghrabi, with some additional remarks by Ulrich Sibiller.