lxsession-defualt apps when launching plank as a dock does not allow access to prefrences.

[Lyn Perrine]

To reproduce install plank a simple dock in lubuntu. Then In defualt applications for lxsession click on core applications and for dock enter in plank. Logout of the session and log back in again. plank will launch however right click on the left most icon that shows plank and prefrences I click the button but the prefrences window will not open.

plank:
  Installed: 0.9.1-1
  Candidate: 0.9.1-1
  Version table:
 *** 0.9.1-1 0
        500 http://us.archive.ubuntu.com/ubuntu/ wily/universe amd64 Packages
        100 /var/lib/dpkg/status
lxsession:
  Installed: 0.5.2-0ubuntu2
  Candidate: 0.5.2-0ubuntu2
  Version table:
 *** 0.5.2-0ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ wily/universe amd64 Packages
        100 /var/lib/dpkg/status
lxsession-default-apps:
  Installed: 0.5.2-0ubuntu2
  Candidate: 0.5.2-0ubuntu2
  Version table:
 *** 0.5.2-0ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ wily/universe amd64 Packages
        100 /var/lib/dpkg/status
Description: Ubuntu Wily Werewolf (development branch)
Release: 15.10

I expected the prefrences window to come up when right clicking on the plank icon for plank. Instead I get no window when plank is autostarted through being the defualt dock in default apps for lxsession. If I start plank through the run dialog in lxpanel and then click on the prefrences icon plank will have the prefrences window show up and I can adjust settings on the dock.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: lxsession 0.5.2-0ubuntu2
ProcVersionSignature: Ubuntu 4.1.0-3.3-generic 4.1.3
Uname: Linux 4.1.0-3-generic x86_64
ApportVersion: 2.18-0ubuntu5
Architecture: amd64
CurrentDesktop: LXDE
Date: Thu Aug 6 12:24:36 2015
InstallationDate: Installed on 2015-06-11 (56 days ago)
InstallationMedia: Lubuntu 15.10 "Wily Werewolf" - Alpha amd64 (20150611)
SourcePackage: lxsession
UpgradeStatus: No upgrade log present (probably fresh install)