Lately an horrible bug with nm-applet into Debian Sid brought me into digging
on various forum, IRC logs and so on.
The issue was a trivial
Failed to add new connection: (32) Insufficient
privileges. error message whenever I tried to activate wifi or any other
connection from the NetworkManager applet in XFCE4.
I was pretty scared about this systemd thread but luckily was enough to create /etc/polkit-1/localauthority/50-local.d/org.freedesktop.NetworkManager.pkla with this content:
[nm-applet] Identity=unix-group:netdev Action=org.freedesktop.NetworkManager.* ResultAny=yes ResultInactive=no ResultActive=yes