Kubuntu Jammy ISO doesn't start welcome screen

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/1958120

I tried recreating this by booting a virtual machine with Ubuntu 21.04 installed with a Kubuntu daily build from 2022-01-17 and I saw the grub boot menu and was able to boot Jammy.

@brian-murray Brian Murray -

Yes you can boot Jammy but you do not get the Kubuntu Welcome screen that allows you to select "Try Kubuntu" or "Install Kubuntu" - instead you go direct to the desktop and of course from there you can the select the Install icon .. also note - when you boot up you get a quick error message on screen
"failed to start Live CD installer" I have tested this on several machines with same results.

I am uploading one of the syslogs showing the error reported and note following entries from the log-

Jan 17 09:03:52 kubuntu systemd[1]: Failed to start Ubuntu live CD installer.
Jan 17 09:03:52 kubuntu systemd[1]: ubiquity.service: Consumed 2.399s CPU time.
Jan 17 09:03:52 kubuntu systemd[1]: Starting Terminate Plymouth Boot Screen...
Jan 17 09:03:52 kubuntu systemd[1]: Finished Terminate Plymouth Boot Screen.
Jan 17 09:03:52 kubuntu systemd[1]: Starting Simple Desktop Display Manager...
Jan 17 09:03:52 kubuntu systemd[1]: Started Simple Desktop Display Manager.
Jan 17 09:03:52 kubuntu sddm[1721]: Initializing...
Jan 17 09:03:52 kubuntu systemd[1]: NetworkManager-dispatcher.service: Deactivated successfull

These two messages, while uninformative, seem relevant.

Jan 17 09:03:51 kubuntu systemd[1]: ubiquity.service: Main process exited, code=exited, status=1/FAILURE
...
Jan 17 09:03:52 kubuntu systemd[1]: ubiquity.service: Failed with result 'exit-code'.
Jan 17 09:03:52 kubuntu systemd[1]: Failed to start Ubuntu live CD installer.

Oh, /var/log/installer/dm has useful information:

biquity-dm: Traceback (most recent call last):
  File "/usr/bin/ubiquity-dm", line 893, in main
    ret = run(vt, display, username)
  File "/usr/bin/ubiquity-dm", line 868, in run
    ret = dm.run(*sys.argv[4:])
  File "/usr/bin/ubiquity-dm", line 730, in run
    breeze = subprocess.Popen(
  File "/usr/lib/python3.9/subprocess.py", line 951, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
  File "/usr/lib/python3.9/subprocess.py", line 1821, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: '/usr/lib/x86_64-linux-gnu//kconf_update_bin/kde4breeze'

(II) Server terminated successfully (0). Closing log file.
Failed to load /usr/share/wallpapers/Next/contents/images/2560x1600.png

Thanks for the clarification on the bug, I was able to recreate it now.

I will prepare a fix

https://code.launchpad.net/~rikmills/ubiquity/+git/ubiquity/+merge/414563

This bug was fixed in the package ubiquity - 22.04.4

---------------
ubiquity (22.04.4) jammy; urgency=medium

  [ Brian Murray ]
  * debian/ubiquity.templates: capitalize Wi-Fi in multiple places so that is
    consistent throughout the installer.
  * tests/*: use a try except so EnvironmentVarGuard can be imported with
    python3.9 or python3.10.

  [ Łukasz 'sil2100' Zemczak ]
  * Add the ability to unhide passwords that are being typed-in during various
    stages (GTK for now).

  [ Rik Mills ]
  * ubiquity-dm: Fix try/install screen for KDE. (LP: #1958120)
    - Remove legacy KDE4 code now that the binary it tries to start was
      removed in latest plasma release.
    - Fix background wallpaper extension. png -> jpg

 -- Brian Murray <email address hidden> Wed, 26 Jan 2022 11:35:06 -0800

Think this was all that was needed to fix things, but some testing to confirm would be great.

The ubiquity version with the fix should be on the next ISO in the morning UK time.

Testing Kubuntu Jammy daily ISO 27-01-2022
http://iso.qa.ubuntu.com/qatracker/milestones/429/builds/243445/testcases/1300/results

I can confirm the fix - the "welcome" screen now appears again as normal.