For some reason update-manager doesn't export the right hints to apt-listchanges, so the process ends up starting "less" instead of a GTK window (which it was configured to do via debconf).
Since the console for update-manager is hidden by default, the user doesn't even notice that the updater is waiting for user input (in this case, paging through, "q", then "y").
Ideally u-m should coax apt-listchanges to show the dialog, or at the very least notice that the operation is stalled and alert the user.
ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: update-manager 1:0.196.3
ProcVersionSignature: Ubuntu 3.12.0-7.15-generic 3.12.4
Uname: Linux 3.12.0-7-generic x86_64
NonfreeKernelModules: openafs
ApportVersion: 2.12.7-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Tue Dec 24 17:14:54 2013
ExecutablePath: /usr/bin/update-manager
GsettingsChanges:
b'com.ubuntu.update-manager' b'show-details' b'true'
b'com.ubuntu.update-manager' b'window-height' b'744'
b'com.ubuntu.update-manager' b'first-run' b'false'
b'com.ubuntu.update-manager' b'window-width' b'1301'
b'com.ubuntu.update-manager' b'launch-time' b'1387922868'
InstallationDate: Installed on 2013-03-18 (281 days ago)
InstallationMedia: Ubuntu 12.04.2 LTS "Precise Pangolin" - Release amd64 (20130214)
InterpreterPath: /usr/bin/python3.3
PackageArchitecture: all
SourcePackage: update-manager
UpgradeStatus: Upgraded to trusty on 2013-11-23 (30 days ago)
---
ApportVersion: 2.12.7-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
DistroRelease: Ubuntu 14.04
InstallationDate: Installed on 2013-03-18 (281 days ago)
InstallationMedia: Ubuntu 12.04.2 LTS "Precise Pangolin" - Release amd64 (20130214)
MarkForUpload: True
NonfreeKernelModules: openafs
Package: apt-listchanges 2.85.11ubuntu1
PackageArchitecture: all
ProcVersionSignature: Ubuntu 3.12.0-7.15-generic 3.12.4
Tags: trusty
Uname: Linux 3.12.0-7-generic x86_64
UpgradeStatus: Upgraded to trusty on 2013-11-23 (30 days ago)
UserGroups: adm cdrom dip fuse kvm libvirtd lpadmin plugdev sambashare sbuild sudo
apport information