What is “startup-notification” Package?

Reference implementation of startup notification protocol
For more details: https://www.freedesktop.org/wiki/Software/startup-notification/

Installation

• Open Terminal by pressing command+space then type terminal and hit Enter key.
• Install homebrew first.

  ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null

• Install startup-notification.

  brew install startup-notification

Now, use startup-notification!