The Desktop Notifications framework provides a standard way of doing passive pop-up notifications on the Linux desktop. These are designed to notify the user of something without interrupting their work with a dialog box that they must close. Passive popups can automatically disappear after a short period of time.
This project consists of a specification (http://www.galago.info/specs/notification/index.php) and a reference implementation (libnotify and notification-daemon).
(see also related pr for deskutils/notification-daemon)
This is actually an port PR.
I'll take this.