software-properties-gtk can't change settings on LXDE

[Andreas Weller]

On 15.04 beta I can't change any settings with software-properties-gtk using the LXDE gui (ie switch off daily update search)
It seems root rights are not applied correctly.
Using sudo /usr/bin/python3 /usr/bin/software-properties-gtk works

** (software-properties-gtk:1617): WARNING **: Error retrieving accessibility bus address: org.freedesktop.DBus.Error.ServiceUnknown: The name org.a11y.Bus was not provided by any .service files

(software-properties-gtk:1617): Gtk-WARNING **: Theme parsing error: gtk-main.css:69:36: Failed to import: Fehler beim Öffnen der Datei: Datei oder Verzeichnis nicht gefunden
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkAlignment:top-padding is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkAlignment:left-padding is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkButton:xalign is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkTreeView:rules-hint is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkButton:use-stock is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkSettings:gtk-button-images is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
ERROR:root:Authentication canceled, changes have not been saved
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkImage:stock is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkAlignment:xscale is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)
/usr/lib/python3/dist-packages/softwareproperties/gtk/utils.py:29: Warning: The property GtkAlignment:yscale is deprecated and shouldn't be used anymore. It will be removed in a future version.
  self.builder.add_from_file(path)

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: software-properties-gtk 0.96.4
ProcVersionSignature: Ubuntu 3.19.0-13.13-generic 3.19.3
Uname: Linux 3.19.0-13-generic x86_64
ApportVersion: 2.17-0ubuntu2
Architecture: amd64
CurrentDesktop: LXDE
Date: Sat Apr 11 15:19:39 2015
ExecutablePath: /usr/bin/software-properties-gtk
InstallationDate: Installed on 2015-03-28 (14 days ago)
InstallationMedia: Lubuntu 15.04 "Vivid Vervet" - Beta amd64 (20150326)
InterpreterPath: /usr/bin/python3.4
PackageArchitecture: all
SourcePackage: software-properties
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Lyn Perrine (walterorlin)]

I am able to work around
 this via the workaround in bug 1424362

[Brian Murray (brian-murray)]

Then this seems to be a duplicate of bug 1424362.