Comment 34 for bug 1542733

Hello Glenn,

First, you should add "Source code" repositories in "Software Sources", take a look at https://help.ubuntu.com/community/Repositories/Ubuntu

Then you should install all dependencies needed to build the network-manager-applet package:

$ sudo apt update
$ sudo apt build-dep network-manager-applet
$ sudo apt install quilt devscripts

The previous steps should now work.