Comment 0 for bug 1882442

output of lsb_release -rd:
Description: Ubuntu 20.04 LTS
Release: 20.04

I recently upgraded from 18.04 to 20.04 and was using MATE. When the upgrade was run my external
HDMI monitor was plugged in, after the update, when I reboot, the internal monitor shows the beginning of the boot process (I deactivated 'silent splash' by editing grub.cfg) then it switches to the HDMI monitor and the internal monitor goes dark. I can also get the tty consoles on the external monitor but not the external monitor.

In MATE it was a real problem because the panel is apparently still on the invisible part of the desktop; I used a tty to install gnome, then I could get the display settings by right-clicking on the desktop, and setting the monitors to mirror, so I can reach applications, etc.

Computer is a Dell Inspiron 3275 AIO with touch screen and Intel on-board video, I think.
I had no problems with Ubuntu 18.04 with MATE.

The problem seems to be similar to this bug:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1874194
but sort of the reverse, in that the internal monitor is the problem.

Thank you for your help.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: linux-image-5.4.0-33-generic 5.4.0-33.37
ProcVersionSignature: Ubuntu 5.4.0-33.37-generic 5.4.34
Uname: Linux 5.4.0-33-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.2
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: david 2012 F.... pulseaudio
 /dev/snd/controlC1: david 2012 F.... pulseaudio
 /dev/snd/controlC0: david 2012 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Sun Jun 7 11:43:37 2020
HibernationDevice: RESUME=UUID=3b1a8a2e-1937-4785-b4bb-49f9a251b292
InstallationDate: Installed on 2020-03-07 (91 days ago)
InstallationMedia: Ubuntu-MATE 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
MachineType: Dell Inc. Inspiron 3275 AIO
ProcFB: 0 amdgpudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-33-generic root=UUID=95b8de7f-9de3-4cea-b947-e135a738948c ro
RelatedPackageVersions:
 linux-restricted-modules-5.4.0-33-generic N/A
 linux-backports-modules-5.4.0-33-generic N/A
 linux-firmware 1.187
SourcePackage: linux
UpgradeStatus: Upgraded to focal on 2020-06-06 (1 days ago)
dmi.bios.date: 03/15/2019
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.7.0
dmi.board.name: 04NJ6P
dmi.board.vendor: Dell Inc.
dmi.board.version: A02
dmi.chassis.type: 13
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 00
dmi.modalias: dmi:bvnDellInc.:bvr1.7.0:bd03/15/2019:svnDellInc.:pnInspiron3275AIO:pvr1.7.0:rvnDellInc.:rn04NJ6P:rvrA02:cvnDellInc.:ct13:cvr00:
dmi.product.family: Inspiron
dmi.product.name: Inspiron 3275 AIO
dmi.product.sku: 0855
dmi.product.version: 1.7.0
dmi.sys.vendor: Dell Inc.