$ sudo apt-get update
$ sudo apt-get install fusionforge-plugin-extsubproj 

fusionforge-plugin-extsubproj is installed in your system.

Make ensure the fusionforge-plugin-extsubproj package were installed using the commands given below,

$ sudo dpkg-query -l | grep fusionforge-plugin-extsubproj *

You will get with fusionforge-plugin-extsubproj package name, version, architecture and description in a table

fusionforge-plugin-extsubproj package basic information: