Installation on Ubuntu/Mint

wget -q -O - https://shop.softmaker.com/repo/linux-repo-public.key | sudo apt-key add -
echo "deb https://shop.softmaker.com/repo/apt wheezy non-free" | sudo tee /etc/apt/sources.list.d/freeoffice.list
sudo apt-get update
sudo apt-get install softmaker-freeoffice-2018