Comment 184 for bug 1297849

I'm sorry, i read https://wiki.ubuntu.com/Testing/EnableProposed but i can't figure out how to install the proposed package. I tried
- Create the file /etc/apt/preferences.d/proposed-updates with this content:
Package: *
Pin: release a=xenial-proposed
Pin-Priority: 400
sudo apt-get upgrade -s
i got "network-manager-gnome (1.2.0-0ubuntu0.16.04.3 Ubuntu:16.04/xenial-updates [amd64])"
is that the correct package? It says
"network-manager-openconnect 1.2.0-0ubuntu0.16.04.1" on
https://launchpad.net/ubuntu/+source/network-manager-openconnect/1.2.0-0ubuntu0.16.04.1
- sudo aptitude -t xenial-proposed
does not work for me, but im on 16.04..
After installing aptitude, it gave me
"The Value 'xenial-proposed' is invalid for APT:: Default-Release as such a release is not available in the sources"

I'm thinking the page about Testing/EnabledProposed needs an update (checkbox-gtk does not work for me too for uploading the hardware profile). In the meantime, could some tell this newbielinux how to install the proposed package? And how to uninstall it after testing?