package grub-pc 2.04-1ubuntu26.9 failed to install/upgrade: installed grub-pc package post-installation script subprocess returned error exit status 1

Sorry not sure if this is helpful. I note https://bugs.launchpad.net/bugs/1916981 but that is a different error code. I had other errors in the upgrade process and was prompted by the GUI to file bugs, including Bug #1922096

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: grub-pc 2.04-1ubuntu26.9
ProcVersionSignature: Ubuntu 4.4.0-206.238-generic 4.4.254
Uname: Linux 4.4.0-206-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
CasperMD5CheckResult: skip
Date: Wed Mar 31 14:36:28 2021
DuplicateSignature:
 package:grub-pc:2.04-1ubuntu26.9
 Setting up friendly-recovery (0.2.41ubuntu0.20.04.1) ...
 /usr/sbin/grub-probe: error: failed to get canonical path of `/dev/sda16'.
 dpkg: error processing package friendly-recovery (--configure):
  installed friendly-recovery package post-installation script subprocess returned error exit status 1
ErrorMessage: installed grub-pc package post-installation script subprocess returned error exit status 1
InstallationDate: Installed on 2014-09-22 (2382 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-206-generic root=UUID=f0d6bca4-fa86-4256-9d83-af1bedfd0829 ro quiet splash vt.handoff=7
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 2.04-1ubuntu26.9 failed to install/upgrade: installed grub-pc package post-installation script subprocess returned error exit status 1
UpgradeStatus: Upgraded to focal on 2021-03-31 (0 days ago)