ubiquity-dm: starting
ubiquity-dm: plymouth
ubiquity-dm: start X ['X', '-br', '-ac', '-noreset', '-nolisten', 'tcp', '-background', 'none', 'vt1', ':0']

X.Org X Server 1.20.8
X Protocol Version 11, Revision 0
Build Operating System: Linux 4.4.0-184-generic i686 Ubuntu
Current Operating System: Linux kubuntu 5.4.0-42-generic #46~18.04.1-Ubuntu SMP Fri Jul 10 07:09:27 UTC 2020 i686
Kernel command line: file=/cdrom/preseed/kubuntu.seed boot=casper maybe-ubiquity initrd=/casper/initrd quiet splash --- maybe-ubiquity
Build Date: 03 July 2020  07:00:25AM
xorg-server-hwe-18.04 2:1.20.8-2ubuntu2.2~18.04.1 (For technical support please see http://www.ubuntu.com/support) 
Current version of pixman: 0.34.0
	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Thu Aug 13 01:15:19 2020
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
resize called 1280 1024
ubiquity-dm: set vars
ubiquity-dm: pam_open_session
ubiquity-dm: dm-scripts
ubiquity-dm: dbus
ubiquity-dm: dconf-service
ubiquity-dm: start frontend kde_ui
ubiquity-dm: paint background
ubiquity-dm: add_ubiquity_kdedir
ubiquity-dm: start kde4breeze
setting widget style: "Breeze" true
ubiquity-dm: kde4breeze exited with code 0
ubiquity-dm: start kwin
ubiquity-dm: start greeter
OpenGL vendor string:                   nouveau
OpenGL renderer string:                 NV4B
OpenGL version string:                  2.1 Mesa 20.0.8
OpenGL shading language version string: 1.20
Driver:                                 Nouveau
GPU class:                              NV40/G70
OpenGL version:                         2.1
GLSL version:                           1.20
Mesa version:                           20.0.8
X server version:                       1.20.8
Linux kernel version:                   5.4
Requires strict binding:                yes
GLSL shaders:                           limited
Texture NPOT support:                   yes
Virtual Machine:                        no
kf5.kcoreaddons.desktopparser: Property type "Url" is not a known QVariant type. Found while parsing property definition for "X-KWin-Video-Url" in "/usr/share/kservicetypes5/kwineffect.desktop"
QXcbConnection: XCB error: 3 (BadWindow), sequence: 926, resource id: 8388624, major code: 3 (GetWindowAttributes), minor code: 0
QXcbConnection: XCB error: 9 (BadDrawable), sequence: 927, resource id: 8388624, major code: 14 (GetGeometry), minor code: 0
QXcbConnection: XCB error: 3 (BadWindow), sequence: 11829, resource id: 14680069, major code: 15 (QueryTree), minor code: 0
ubiquity-dm: greeter exited with code 1
ubiquity-dm: Failed with an exception:
ubiquity-dm: Traceback (most recent call last):
  File "/usr/bin/ubiquity-dm", line 881, in main
    ret = run(vt, display, username)
  File "/usr/bin/ubiquity-dm", line 856, in run
    ret = dm.run(*sys.argv[4:])
  File "/usr/bin/ubiquity-dm", line 745, in run
    db = DebconfCommunicator('ubiquity', cloexec=True)
  File "/usr/lib/ubiquity/ubiquity/debconfcommunicator.py", line 37, in __init__
    write=self.dccomm.stdin)
  File "/usr/lib/python3/dist-packages/debconf.py", line 71, in __init__
    self.setUp(title)
  File "/usr/lib/python3/dist-packages/debconf.py", line 74, in setUp
    self.version = self.version(2)
  File "/usr/lib/python3/dist-packages/debconf.py", line 83, in <lambda>
    lambda *args, **kw: self.command(command, *args, **kw))
  File "/usr/lib/python3/dist-packages/debconf.py", line 104, in command
    status = int(status)
ValueError: invalid literal for int() with base 10: ''

The X11 connection broke (error 1). Did the X11 server die?
The X11 connection broke (error 1). Did the X11 server die?
(II) Server terminated successfully (0). Closing log file.