indicator-session software package provides indicator showing session management, status and user switching, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install indicator-session
indicator-session is installed in your system.
Make ensure the indicator-session package were installed using the commands given below,
$ sudo dpkg-query -l | grep indicator-session *
You will get with indicator-session package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | GNOME |
| Package | indicator-session |
| Version | 12.10.5+16.04.20160412-0ubuntu |
| Description | indicator showing session management, status and user switching |
| Sub Section | GNOME |