Installing Shadow .deb package on Debian or Ubuntu based distributions
Please refer to the instructions according to the environment of your Shadow: PROD, BETA, or ALPHA.
The easiest way to install Shadow for Debian/Ubuntu-based distributions is to download and install the .deb package (64-bit), either through the graphical software center if it's available, or through the command line.
Installing the .deb package will automatically install the apt repository and signing key to enable auto-updating using the system's package manager.
Alternatively, the repository and key can also be installed manually with the following script: