package friendly-recovery 0.2.31ubuntu2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[redcar]

error during do-release-upgrade in WSL

From: 16.04.5 LTS
To: 18.04.1 LTS
Expected result: working 18.04.1 LTS running in WSL
Acutal result: errors during upgrade and reported version still 16.04.5 LTS

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: friendly-recovery 0.2.31ubuntu2
ProcVersionSignature: Microsoft 4.4.0-18277.1000-Microsoft 4.4.35
Uname: Linux 4.4.0-18277-Microsoft x86_64
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
Date: Wed Nov 14 18:08:35 2018
Dmesg: [ 0.012195] Microsoft 4.4.0-18277.1000-Microsoft 4.4.35
DuplicateSignature:
 package:friendly-recovery:0.2.31ubuntu2
 Setting up friendly-recovery (0.2.31ubuntu2) ...
 /usr/sbin/grub-probe: error: failed to get canonical path of `rootfs'.
 dpkg: error processing package friendly-recovery (--configure):
  subprocess installed post-installation script returned error exit status 1
ErrorMessage: subprocess installed post-installation script returned error exit status 1
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.5
 apt 1.2.29
SourcePackage: grub2
Title: package friendly-recovery 0.2.31ubuntu2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to xenial on 2018-11-14 (0 days ago)
upstart.friendly-recovery.override: manual

[Launchpad Janitor (janitor)]

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

[K. Mehta (kismetkm)]

none