On upgrading 18.04 -> 20.04: package grub-pc 2.04-1ubuntu26.8 failed to install/upgrade: loop on configure dialog

[Daniele Napolitano]

I'm on a VM from LINUXVMIMAGES.COM.

On upgrading from Ubuntu 18.04 to 20.04 the installation of grub-pc detectedt a different media giving me the option to delect another drive where install grub. Even selecting a drive (correct one) the dialog ask me to proceed without installing grub. This dialog looped through those screens, in the end I used xkill to complete the upgrade.

In the end, with "dpkg configure -a" I was able to complete the configuration of grub-pc through the the ncurses dialog.

So, seems broken the gui configure dialog.

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: grub-pc 2.04-1ubuntu26.8
ProcVersionSignature: Ubuntu 5.4.0-65.73-generic 5.4.78
Uname: Linux 5.4.0-65-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
CasperMD5CheckResult: skip
Date: Sat Feb 6 11:24:49 2021
ErrorMessage: installed grub-pc package post-installation script subprocess returned error exit status 1
InstallationDate: Installed on 2020-10-18 (110 days ago)
InstallationMedia: Ubuntu 18.04.5 LTS "Bionic Beaver" - Release amd64 (20200806.1)
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-65-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash
Python3Details: /usr/bin/python3.8, Python 3.8.5, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.4
SourcePackage: grub2
Title: package grub-pc 2.04-1ubuntu26.8 failed to install/upgrade: installed grub-pc package post-installation script subprocess returned error exit status 1
UpgradeStatus: Upgraded to focal on 2021-02-06 (0 days ago)