Hello,
It worked for me!
Thanks
Alberto

On Tue, Jul 28, 2020 at 3:55 AM Daniel van Vugt <email address hidden>
wrote:

> Please tell us if this also works around the problem:
>
> 1. Edit /etc/gdm3/custom.conf and uncomment:
>
>    #WaylandEnable=false
>
>    so it is now:
>
>    WaylandEnable=false
>
> 2. Reboot.
>
>
> ** Also affects: gdm3 (Ubuntu)
>    Importance: Undecided
>        Status: New
>
> ** Also affects: mutter (Ubuntu)
>    Importance: Undecided
>        Status: New
>
> ** Changed in: plymouth (Ubuntu)
>        Status: Triaged => Confirmed
>
> ** Changed in: mutter (Ubuntu)
>    Importance: Undecided => High
>
> ** Changed in: gdm3 (Ubuntu)
>    Importance: Undecided => High
>
> ** Changed in: gdm3 (Ubuntu)
>        Status: New => Confirmed
>
> ** Changed in: mutter (Ubuntu)
>        Status: New => Confirmed
>
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (1874194).
> https://bugs.launchpad.net/bugs/1872159
>
> Title:
>   booting with splash hangs when external monitors are connected
>
> Status in Plymouth:
>   Unknown
> Status in gdm3 package in Ubuntu:
>   Confirmed
> Status in mutter package in Ubuntu:
>   Confirmed
> Status in plymouth package in Ubuntu:
>   Confirmed
>
> Bug description:
>   I think this is a problem with the splash boot loader. This problem is
>   not reproduced if using nosplash.
>
>   I have installed 20.04 to this laptop. Thinkpad T480, i7, intel
>   graphics.
>
>   Clean install of 20.04 beta, not an upgrade.
>   When booting from the install, the greeter screen is never reached if
> external monitors are connected at startup.
>   I get the spinning ubuntu logo, and nothing more. I can not change to
> virtual terminals. The fsck step does not commence.
>
>   In recovery mood, I can log in.
>
>   With no external monitors attached, it works.
>
>   I am used to having such problems with Nvidia graphics is involved,
>   but this is not the case on this laptop. It has been happily running
>   18.04.
>
>   External displays are recognised if they are connected after login.
>
>   Also, when I edit /etc/default/grub so that it reads
>   GRUB_CMDLINE_LINUX_DEFAULT=""
>   (that is, splash disabled)
>   it works fine with two external monitors attached.
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 20.04
>   Package: xorg 1:7.7+19ubuntu14
>   ProcVersionSignature: Ubuntu 5.4.0-21.25-generic 5.4.27
>   Uname: Linux 5.4.0-21-generic x86_64
>   ApportVersion: 2.20.11-0ubuntu26
>   Architecture: amd64
>   BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
>   CasperMD5CheckResult: skip
>   CompositorRunning: None
>   CurrentDesktop: ubuntu:GNOME
>   Date: Sat Apr 11 13:58:19 2020
>   DistUpgraded: Fresh install
>   DistroCodename: focal
>   DistroVariant: ubuntu
>   DkmsStatus:
>    acpi-call, 1.1.0, 5.4.0-21-generic, x86_64: installed
>    tp_smapi, 0.43, 5.4.0-21-generic, x86_64: installed
>   ExtraDebuggingInterest: Yes, including running git bisection searches
>   GraphicsCard:
>    Intel Corporation UHD Graphics 620 [8086:5917] (rev 07) (prog-if 00
> [VGA controller])
>      Subsystem: Lenovo UHD Graphics 620 [17aa:225d]
>   InstallationDate: Installed on 2020-04-10 (0 days ago)
>   InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Beta amd64 (20200402)
>   MachineType: LENOVO 20L5S00F00
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-21-generic
> root=/dev/mapper/myvg-root ro
>   SourcePackage: xorg
>   Symptom: display
>   UpgradeStatus: No upgrade log present (probably fresh install)
>   dmi.bios.date: 02/19/2020
>   dmi.bios.vendor: LENOVO
>   dmi.bios.version: N24ET56W (1.31 )
>   dmi.board.asset.tag: Not Available
>   dmi.board.name: 20L5S00F00
>   dmi.board.vendor: LENOVO
>   dmi.board.version: Not Defined
>   dmi.chassis.asset.tag: No Asset Information
>   dmi.chassis.type: 10
>   dmi.chassis.vendor: LENOVO
>   dmi.chassis.version: None
>   dmi.modalias:
> dmi:bvnLENOVO:bvrN24ET56W(1.31):bd02/19/2020:svnLENOVO:pn20L5S00F00:pvrThinkPadT480:rvnLENOVO:rn20L5S00F00:rvrNotDefined:cvnLENOVO:ct10:cvrNone:
>   dmi.product.family: ThinkPad T480
>   dmi.product.name: 20L5S00F00
>   dmi.product.sku: LENOVO_MT_20L5_BU_Think_FM_ThinkPad T480
>   dmi.product.version: ThinkPad T480
>   dmi.sys.vendor: LENOVO
>   version.compiz: compiz N/A
>   version.libdrm2: libdrm2 2.4.101-1
>   version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.4-1ubuntu1
>   version.libgl1-mesa-glx: libgl1-mesa-glx 20.0.4-1ubuntu1
>   version.xserver-xorg-core: xserver-xorg-core 2:1.20.7-2ubuntu2
>   version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
>   version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
>   version.xserver-xorg-video-intel: xserver-xorg-video-intel
> 2:2.99.917+git20190815-1
>   version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1
>
> To manage notifications about this bug go to:
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>