Xubuntu 16.10 ubiquity crashed with dbus.exceptions.DBusException in call_blocking(): org.freedesktop.NetworkManager.Settings.PermissionDenied: Insufficient privileges.

[Set Hallstrom]

Xubuntu 16.10 development version 20160806. ISO checksum exclude download error.

Reproduce:
Boot up using USB-key.
At boot, the menu to choose between install- or live-session lacks any button to make selection. Press the X to close the window en enter the live-session
Double click "Install" icon on desktop.
Choose WIFI and enter password

Result: Ubiquity crashes.

Side Note:
Desktop Environment had same problem as Ubuntu Studio in https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1610377

ProblemType: Crash
DistroRelease: Ubuntu 16.10
Package: ubiquity 16.10.5
ProcVersionSignature: Ubuntu 4.4.0-33.52-generic 4.4.15
Uname: Linux 4.4.0-33-generic x86_64
ApportVersion: 2.20.3-0ubuntu5
Architecture: amd64
CasperVersion: 1.376
CrashCounter: 1
Date: Sat Aug 6 10:31:09 2016
ExecutablePath: /usr/lib/ubiquity/bin/ubiquity
InstallCmdLine: file=/cdrom/preseed/xubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --- maybe-ubiquity
InterpreterPath: /usr/bin/python3.5
LiveMediaBuild: Xubuntu 16.10 "Yakkety Yak" - Alpha amd64 (20160806)
ProcCmdline: /usr/bin/python3 /usr/lib/ubiquity/bin/ubiquity gtk_ui
ProcEnviron: Error: [Errno 13] Permission denied: '/proc/8548/environ'
PythonArgs: ['/usr/lib/ubiquity/bin/ubiquity', 'gtk_ui']
SourcePackage: ubiquity
Title: ubiquity crashed with dbus.exceptions.DBusException in call_blocking(): org.freedesktop.NetworkManager.Settings.PermissionDenied: Insufficient privileges.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1047657, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.