package vanilla-gnome-default-settings 18.10.1 failed to install/upgrade: installed vanilla-gnome-default-settings package post-installation script subprocess returned error exit status 2

[Norbert]

sudo apt-get install *gnome* --install-suggests --install-recommends

ends with message about missed alternatives for gdm3.css

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: vanilla-gnome-default-settings 18.10.1
ProcVersionSignature: Ubuntu 5.4.0-21.25-generic 5.4.27
Uname: Linux 5.4.0-21-generic x86_64
ApportVersion: 2.20.11-0ubuntu22
Architecture: amd64
Date: Sat Apr 4 11:14:48 2020
DuplicateSignature:
 package:vanilla-gnome-default-settings:18.10.1
 Setting up ubuntustudio-gnome-branding (20.04) ...
 update-alternatives: error: no alternatives for gdm3.css
 dpkg: error processing package ubuntustudio-gnome-branding (--configure):
  installed ubuntustudio-gnome-branding package post-installation script subprocess returned error exit status 2
ErrorMessage: installed vanilla-gnome-default-settings package post-installation script subprocess returned error exit status 2
PackageArchitecture: all
Python3Details: /usr/bin/python3.8, Python 3.8.2, python3-minimal, 3.8.2-0ubuntu1
PythonDetails: N/A
RelatedPackageVersions:
 dpkg 1.19.7ubuntu2
 apt 2.0.1
SourcePackage: ubuntu-gnome-default-settings
Title: package vanilla-gnome-default-settings 18.10.1 failed to install/upgrade: installed vanilla-gnome-default-settings package post-installation script subprocess returned error exit status 2
UpgradeStatus: Upgraded to focal on 2020-04-03 (0 days ago)