The non-recovery=standard boot let hangup the cursor after login after some seconds.

[Pierre Lauber]

I am forced currently to use the recovery boot which seems to work still at least.

In the standard boot (in grub selecting not the recovery boot menu item) after login in the desktop, the cursor gets stuck after some seconds. No chance to get it moving
again whether in graphics or text/terminal mode.
I was exchanging all HMI devices, so, monitor, kbd and mouse. Same problem.

The first time, it happened after incremental upgrade from 22.04 to 22.10 to 23.04.
Finally, I downloaded the ISO image of 23.04 desktop amd64 and using etcher I created a bootable usb stick. Latter (non-incremental) absolute install worked as well but finally ended up in the same problem.

Please let me get out of recovery boot desktop :-)

ProblemType: Bug
DistroRelease: Ubuntu 23.04
Package: ubuntu-release-upgrader-core 1:23.04.5
ProcVersionSignature: Ubuntu 6.2.0-20.20-generic 6.2.6
Uname: Linux 6.2.0-20-generic x86_64
ApportVersion: 2.26.1-0ubuntu2
Architecture: amd64
CasperMD5CheckResult: unknown
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sat Apr 22 16:21:15 2023
InstallationDate: Installed on 2023-04-22 (0 days ago)
InstallationMedia: Ubuntu 23.04 "Lunar Lobster" - Release amd64 (20230418)
PackageArchitecture: all
ProcEnviron:
 LANG=en_US.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 XDG_RUNTIME_DIR=<set>
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: No upgrade log present (probably fresh install)

[Pierre Lauber (pilauber)]

1. Without recovery (=verbose kernel) boot, I found a clear problem indicator.
After login sometimes some seconds last before the cursor stuck.
But always very shortly before the cursor stuck for about five seconds, one can see at the
top gnome desktop task bar following:
On the top screen area within the small task bar and up to about the double height of the task bar
below the task bar, random pixels in random colors are written to the video memory.
After that, the system is locked. Last Update on 25th June 2023. It did not change with the last
updates. The phenomenon is reproducible.
It seems something is wrongly overwriting the video memory. Ok, the problem comes with the upgrade,
but, it might refer to frame buffer, X11, gnome or gtk etc.

2. I found a workaround for 1.
Using recovery boot (=verbose kernel boot) and selecting "resume" (to normal (high resolution)
boot) in the appearing pop-up, the problem of 1. does not happen at all and one can work as usual.

3. Because of 2., I was able to proceed and I found another bug: The hotspot does not work. (In 22.04 it worked)
Additional dkms install for my rtl8821cu NIC as in 22.04 (the standard community support) did not
solve.

[Pierre Lauber (pilauber)]

Addendum concerning my still confirmed points of above
1. still remains and is still open for fixing.
(The vmlinuz kernel command line without the recovery option is responsible for overwriting (video) memory? Maybe try some bounds-checking here.)

2. No eye catching output during the recovery=verbose kernel boot especially no error messages, everything got OK.
This workaround works reliably currently.

3. Bluetooth does not work as well. It seems this is Ubuntu Bug #1886169. The latter disappeared by upgrades but the real cause and fix was not found. So, this bug is back again. (Compared with point 2., this bug is really annoying and might be easier to fix.)

[Pierre Lauber (pilauber)]

Updates as of 20.9.2023 applied.

1. In standard=non-recovery=not verbose kernel boot mode:
 Absolute bug description:
  At least after login, one can work sometimes a lot and a long time.
  But sometimes, the mouse freezes suddenly again as described.
  I found only one systematic up to now: The risk that the mouse freezes is higher in the
  region where usually the dock is located (on the left side of the screen).
  (I am using hide dock where ever possible)

 Relative bug description (Changes): The bug reduced to the region where the dock is located.
  If the mouse is inside of the dock region (especially although it is not visible)
  the screen freezes entirely as described.

2. Recovery=Kernel verbose boot mode:
  seems not to have the bug at all (as already described).

[Pierre Lauber (pilauber)]

1. Unchanged. The problem in principle persists.
The crash in the dock region happens rarely, but it is still there in Ubuntu 23.04 and 23.10,
and also in 22.04 LTS (bad fix merged in as well?)!

[Launchpad Janitor (janitor)]

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