No try/install dialogue displayed

[Elfy]

Running 32vivid Xubuntu in VBox running in vivid.

Boots to a blank desktop - should boot to our Try/Install Dialogue.

Only apparent in vbox, running the same image from usb on hardware and it works.

Reported this via vt1 and apport-cli

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: ubiquity 2.21.10
ProcVersionSignature: Ubuntu 3.18.0-13.14-generic 3.18.5
Uname: Linux 3.18.0-13-generic i686
ApportVersion: 2.16.1-0ubuntu2
Architecture: i386
CasperVersion: 1.351
Date: Wed Feb 18 12:40:14 2015
InstallCmdLine: file=/cdrom/preseed/xubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
LiveMediaBuild: Xubuntu 15.04 "Vivid Vervet" - Alpha i386 (20150218)
ProcEnviron:
 SHELL=/bin/bash
 TERM=linux
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 XDG_RUNTIME_DIR=<set>
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1423161

[Brian Murray (brian-murray)]

Setting to High since it only appears in Vbox.

[Jack Fromm (jjfrv8)]

Also affects the 64-bit version in the 20150219 build.

[Elfy (elfy)]

64bit 20150220 build in vbox works.

Issue not apparent using kvm - however, that appears to hang at the first boot screen waiting for user input rather than carrying through to the try/install dialougue.

[Elfy (elfy)]

/var/log/installer/debug

http://pastebin.ubuntu.com/10328649/

[Elfy (elfy)]

/var/log/installer/dm

http://pastebin.ubuntu.com/10328655/

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubiquity - 2.21.12

---------------
ubiquity (2.21.12) vivid; urgency=medium

  * Clean up after NetworkManager's system-connections files in prepare job
    for oem-config: we shouldn't keep wireless connections (or any, really)
    on the system that may have been setup by OEM, unless done *after* running
    oem-prepare. (LP: #1418105)
  * Force the GTK-based installer to be visible when starting, this should fix
    it being running but hidden on some Xubuntu only-ubiquity installs, which
    meant users had to Alt-Tab to it and switch language for it to appear.
    (LP: #1423161)
  * Automatic update of included source packages: grub-installer
    1.78ubuntu25.
 -- Mathieu Trudel-Lapierre <email address hidden> Fri, 20 Feb 2015 17:15:16 -0500