I just installed KDE Neon User and there is no sources listed in the Discover application and I can't install software. If I open neon.list in /etc/apt/souces.list.d I do see two listed. deb http://archive.neon.kde.org/user xenial main deb-src http://archive.neon.kde.org/user xenial main Reproducible: Always Steps to Reproduce: 1. Open Discover 2. Click hotdog menu 3. Click Configure Sources
I am on 5.7, this still happens. Although you can make discover display them.... Do: ALT+S > hit the "+" button> Software manager, a box will pop. Don't click or type anything, wait a few seconds and they will appear. Then you'll encounter this: https://bugs.kde.org/show_bug.cgi?id=327178
Sources support landed later this summer, should be in in last versions.