$ sudo apt-get update
$ sudo apt-get install libknotifyconfig4 

libknotifyconfig4 is installed in your system.

Make ensure the libknotifyconfig4 package were installed using the commands given below,

$ sudo dpkg-query -l | grep libknotifyconfig4 *

You will get with libknotifyconfig4 package name, version, architecture and description in a table

libknotifyconfig4 package basic information: