ejabberd-contrib software package provides user-contributed modules for ejabberd (metapackage), 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 ejabberd-contrib
ejabberd-contrib is installed in your system.
Make ensure the ejabberd-contrib package were installed using the commands given below,
$ sudo dpkg-query -l | grep ejabberd-contrib *
You will get with ejabberd-contrib package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | ejabberd-contrib |
| Version | 0.2016.09.12~dfsg0-2 |
| Description | user-contributed modules for ejabberd (metapackage) |
| Sub Section | Net |