You can uninstall or removes an installed gnats-user package itself from Ubuntu 16.04 LTS (Xenial Xerus) through the terminal,
$ sudo apt-get remove gnats-user
If you would like to remove gnats-user and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove gnats-user
If you use with purge options to gnats-user package all the configuration and dependent packages will be removed.
$ sudo apt-get purge gnats-user
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove gnats-user
I'm very pleased to share my working experience in the Linux field and have posted articles in this website — bits and pieces learned throughout my career.
