cinnamon-session-common software package provides Cinnamon Session Manager - common files, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install cinnamon-session-common
cinnamon-session-common is installed in your system.
Make ensure the cinnamon-session-common package were installed using the commands given below,
$ sudo dpkg-query -l | grep cinnamon-session-common *
You will get with cinnamon-session-common package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | X Window System software |
| Package | cinnamon-session-common |
| Version | 3.0.1-2 |
| Description | Cinnamon Session Manager - common files |
| Sub Section | x11 |