## Debian 9
sudo apt install -y lsb-release wget apt-transport-https
sudo wget -O /usr/share/keyrings/riot-im-archive-keyring.gpg https://packages.riot.im/debian/riot-im-archive-keyring.gpg
echo "deb [signed-by=/usr/share/keyrings/riot-im-archive-keyring.gpg] https://packages.riot.im/debian/ $(lsb_release -cs) main" |
    sudo tee /etc/apt/sources.list.d/riot-im.list
sudo apt update
sudo apt install riot-web

## Debian 8
#sudo apt install -y lsb-release wget apt-transport-https
#sudo wget -O /etc/apt/trusted.gpg.d/riot-im-archive-keyring.gpg https://packages.riot.im/debian/riot-im-archive-keyring.gpg
#echo "deb [signed-by=75741890063E5E9A46135D01C2850B265AC085BD] https://packages.riot.im/debian/ $(lsb_release -cs) main" |
#    sudo tee /etc/apt/sources.list.d/riot-im.list
#sudo apt update
#sudo apt install riot-web