update-manager window blank; pkgs_install_oem problem

[Chris Hermansen]

Ubuntu 20.04, since approximately Nov 2020.

The second window in the update-manager workflow is blank - no active but invisible controls, no selectable but invisible text.

When I run update-manager from the terminal I see this traceback:

$ update-manager
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/UpdateManager/Dialogs.py", line 118, in <lambda>
    button.connect("clicked", lambda x: callback())
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdatesAvailable.py", line 880, in on_button_install_clicked
    self.window_main.start_install()
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 234, in start_install
    self._start_pane(install_backend)
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 174, in _start_pane
    pane.start()
  File "/usr/lib/python3/dist-packages/UpdateManager/backend/__init__.py", line 61, in start
    self.commit_oem(pkgs_install_oem, pkgs_upgrade_oem)
UnboundLocalError: local variable 'pkgs_install_oem' referenced before assignment
$

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: update-manager 1:20.04.10.2
ProcVersionSignature: Ubuntu 5.8.0-7630.32~1609193707~20.04~781bb80~dev-generic 5.8.17
Uname: Linux 5.8.0-7630-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.14
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Fri Jan 8 10:51:35 2021
PackageArchitecture: all
SourcePackage: update-manager
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.default.apport:
 # set this to 0 to disable apport, or to 1 to enable it
 # you can temporarily override this with
 # sudo service apport start force_start=1
 enabled=0
mtime.conffile..etc.default.apport: 2018-10-18T16:46:45.176415

[Chris Hermansen (c-hermansen)]

I probably should have added that apt update & apt upgrade seem to work fine

[Julian Andres Klode (juliank)]

+update-manager (1:21.04.3) hirsute; urgency=medium
+
+ [ Brian Murray ]
+ * UpdateManager/Dialogs.py: do not mention livepatch settings when the
+ interface is not installed, thanks to Sebastien Bacher for the patch.
+ (LP: #1807900)
+ * UpdateManager/backend/__init__.py: Resolve unbound local error crash with
+ oem package lists. Thanks to Thomas Bechtold for the patch.
+