libindicator-dev software package provides panel indicator applet - library development files, you can install in your Debian 8 (Jessie) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libindicator-dev
libindicator-dev is installed in your system.
Make ensure the libindicator-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep libindicator-dev *
You will get with libindicator-dev package name, version, architecture and description in a table
| Distro | Debian 8 jessie |
| Section | Library development |
| Package | libindicator-dev |
| Version | 0.5.0-2 |
| Description | panel indicator applet - library development files |
| Sub Section | Libdevel |