Comment 16 for bug 1404188

There's now a PPA with a Qt build for vivid+overlay that allows you to experiment with the option of not using the NM bearer backend but the generic backend (with very limited functionality compared). With that you can get "all is fine" even with a click installed / confined nmsessiontest app. But this does bring the notorious bug #1357321 back. However, for comparison:

https://launchpad.net/~canonical-qt5-edgers/+archive/ubuntu/qt5-daily

That is:
sudo apt-add-repository ppa:canonical-qt5-edgers/qt5-daily
sudo apt update
sudo vi /etc/apt/preferences.d/silotest.pref
# Add the following content to the file:
Package: *
Pin: release o=LP-PPA-canonical-qt5-edgers-qt5-daily
Pin-Priority: 1002

sudo apt upgrade

The mentioned -no-feature-bearermanagement is a non-standard configuration parameter that is probably only suitable for specialized builds, so that can't even be considered for a general Ubuntu build. At least it broke building various network tests of the default test enable build: http://is.gd/YGcaY8 http://is.gd/TFSdQ1