booting lubuntu noble daily and getting black screen + wallpaper but no try/install dialog

[Chris Guiver]

lubuntu daily booted on
- hp prodesk 400 g1 sff (i5-4570, 8gb, amd/ati cedar radeon hd 5000/6000/7350/8350)

two displays, on boot I get black screen on one display & wallpaper background on other. it just sits there. (I've rebooted a couple of times & getting the same)

** expected outcome

I expect the TRY or INSTALL selection dialog

** actual results

alas just black screen + wallpaper appears, with nothing else viewable

** to fix

to get the TRY/INSTALL dialog; I needed to hit ALT+TAB and then I have the TRY/INSTALL dialog appear on top of the wallpaper screen
---
ProblemType: Bug
ApportVersion: 2.27.0-0ubuntu6
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.490
CurrentDesktop: LXQt
DistroRelease: Ubuntu 24.04
LiveMediaBuild: Lubuntu 24.04 LTS "Noble Numbat" - Daily amd64 (20231225)
Package: lubuntu-installer-prompt 1.1.1-0ubuntu2
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 6.5.0-9.9-generic 6.5.3
Tags: noble third-party-packages
Uname: Linux 6.5.0-9-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo users
_MarkForUpload: True

[Chris Guiver (guiverc)]

apport information

[Chris Guiver (guiverc)]

apport information

[Chris Guiver (guiverc)]

apport information

[Chris Guiver (guiverc)]

Identical results when booted on
- hp 8200 elite sff (i5-2400, 8gb, nvidia quadro 600)

again (and as expected) ALT+TAB allowed me to continue

[Chris Guiver (guiverc)]

Booted Lubuntu noble daily on
- dell [optiplex] 755 (c2d-e6850, 5gb, amd/ati radeon rv516/x1300/x1550)
- lenovo thinkpad x201 (i5-m520, 4gb, i915)

both of which had only single screen connected; no issues here !!

Issues appear to be only on boxes with two(+) screens connected

[Chris Guiver (guiverc)]

Nope, more involved than the number of screens connected

No issue on
- hp dc7700 (c2d-e6320, 8gb amd/ati rv610/radeon hd2400 pro/xt)

with TWO SCREENS connected.

[Chris Guiver (guiverc)]

This issue did occur on

- dell [optiplex] 780 (c2q-q9400, 8gb, amd/ati cedar radeon hd 5000/6000/7350/8350)

(dc7700 & d780 use same screens; one impacted the other isn't, so likely unrelated to screen proportions; though that feels unlikely anyway)

the wallpaper image appeared on 16:10 screen; the 3:4 screen was black on this box.. the wallpaper image was tiled (different resolutions possibly) and looks weird, but i don't care. Four wallpapers appear partially (top left is full).

On hitting ALT+TAB the try/install dialog appeared; it was full screen (not showing only on top left corner wallpaper, but across the background(s))

[Launchpad Janitor (janitor)]

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

[sudodus (nio-wiklund)]

Tested in an HP Probook 640 G4 with

- Intel i5-8250U CPU
- Intel 'UHD Graphics 6'
- built-in resolution 1366x768

connected to an old Samsung monitor with 1920x1080 resolution and the full resolution was used in both screens after alt+tab twice (once to get be able to select language and live session, and once to see the live session. I intend to attach pictures ...

Edit: I should also mention, that the extermal screen is connected via HDMI (a HDMI to HDMI cable).

[sudodus (nio-wiklund)]

At first, before any attempt with alt+tab

[sudodus (nio-wiklund)]

After first attempt with alt+tab: Now I see the screen where to select language and choose live session or installation, but only in the external screen.

[sudodus (nio-wiklund)]

After second attempt with alt+tab: Now I see the desktop both in the external screen and the internal screen and things seem to work as expected.

[sudodus (nio-wiklund)]

By the way, I would like to expand this bug to affect also Lubuntu 23.10 when installed.

After testing Lubuntu Noble live, I was curious about the system that is installed in the HP Probook 640 G4. It works smoothly when booted as usual (with only the internal screen). Now, when booting with the external screen connected, it failed to show anything (nothing on any of the screens except a white underscore on the internal screen). Alt+tab did not help.

I rebooted brutally with ctrl+alt+delete, disconnected the external screen and things worked well. When logged in, I cnnnected the external screen, and then things worked as expected. I had the correct backgrund and could use both screens.

Edit: This was maybe 'only' a temporary glitch after the failures with Lubuntu Noble live. See comment #15.

[Simon Quigley (tsimonq2)]

Usually, I would agree. There's a general issue that affects more than one release. That being said, this bug is specific to the installer prompt (and its rendering on more than one display), so I think we should address these two issues separately.

Let's keep this bug targeted to Noble; please add another package (I guess that may be lxqt-session for now) and try to grab as many details as possible from syslog, the systemd journal, and friends. See if the safe graphics mode works. Try switching to a TTY. Does Plymouth show on both displays? Both of you are seasoned and trusted in QA, you get the point. :)

Please let me know how I can help. For the time being, I've marked the installer prompt part of this bug as triaged/critical/assigned to the dev team; we'll solve that in week one of January.

[sudodus (nio-wiklund)]

OK. Simon,

I prepared for making a separate bug report for problems with 2 screens in Lubuntu 23.10. And there was a nice surprise: It works, when cold booted, also when the external screen is connected. My only explanation is that some bad state in some electronic component(s) of the system was not cleared by the brutal reboot (ctrl+alt+delete) after the failure with Lubuntu Noble live.

I will repeat reboot and cold boot a few times to see if things continue to work well. Otherwise I will make a separate bug report.

-o-

After further testing I would say that the function is flaky with two screens connected and the external one turned on at boot and I created

bug report #2047456 "Installed Lubuntu Mantic is flaky with two screens"

[Simon Quigley (tsimonq2)]

You're the best Nio, thank you. :)

[sudodus (nio-wiklund)]

Ubuntu Desktop Noble live was tested in an HP Probook 640 G4 with

- Intel i5-8250U CPU
- Intel 'UHD Graphics 6'
- built-in resolution 1366x768

connected to an old Samsung monitor with 1920x1080 resolution. The external screen is connected via HDMI (a HDMI to HDMI cable). This is the same setup as in comment #9 report except that Ubuntu Desktop was tested instead of Lubuntu.

1,2,3. I booted in UEFI mode with secure boot, when the external Samsung screen was connected. The grub menu was only shown on the internal screen but starting with the splash the external screen worked as expected.

This test shows that standard Ubuntu Desktop Noble works while Lubuntu Noble is flaky in a laptop when an external screen is connected.

See more tests of installed as well as live systems with an external screen connected at bug report #2047456 "Installed Lubuntu Mantic and Noble are flaky with two screens"

[sudodus (nio-wiklund)]

New iso file:

1. Dell Latitude 3520 connected to an external screen: alt+tab needed

2. Toshiba Satellite Pro C850-19W connected to an external screen: The grub menu is 'back' to pure text mode and it works again. This is an important improvement from the previous daily iso file (no longer completely black and alt+tab fixes the remaining problem of the live system) :-)

-o-

I think the same tweak(s), that was used with grub in the live session might help also when applied to the installed system to make it work in the old Toshiba.

[Colin (colin-pyper)]

Ubuntu 24.04 (Noble Numbat) Daily Build shows a large white rectangle or grey rectangle in dark mode where the try or install Ubuntu screen would normally show. This happens whether running from a live USB or trying to install as a virtual machine. It has only started doing this recently as the installer worked ok a few weeks ago.

[Aaron Rainbolt (arraybolt3)]

Turns out the code I wrote for positioning the screens wasn't actually positioning the primary screen at all. 🤪 Fix made and uploaded to Git, once it's uploaded this should be rectified.

[Launchpad Janitor (janitor)]

This bug was fixed in the package lubuntu-installer-prompt - 1.1.2-0ubuntu1

---------------
lubuntu-installer-prompt (1.1.2-0ubuntu1) noble; urgency=medium

  * New upstream release (LP: #2047379).

 -- Simon Quigley <email address hidden> Mon, 01 Jan 2024 13:56:49 -0600

[sudodus (nio-wiklund)]

Fix confirmed by testing in my Toshiba Satellite Pro C850-19W in UEFI mode with an external screen connected.

The main problem of this bug is fixed, but I noticed with different resolutions of the two screens, the try/install dialog has tiled wallpaper on higher resolution screen. After selecting the live session, both screens had correct wallpapers (the photo of the numbat displayed correctly).

In a Dell Latitude E7240 with the same resolution of the the internal screen and the external screen, both screens had correctly rendered wallpapers also 'during' the try/install dialog.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/2047379