The -notifications Ayatana System Indicator is an optional indicator that can collect system notifications (e.g. while having been away from keyboard. It also features filtering out notifications from specific applications and provides a do-not-disturb feature (currently only functional on the MATE desktop environment).
For instructions on building, see the INSTALL file.
The -notifications Ayatana System Indicator has been written by Jason Conti (originally as an Ubuntu System Indicator). This project has been published under the GPL-3+ license (see COPYING file).