Bug 514087

Summary:	On Kubuntu 25.10 With the default KDE desktop: After monitor sleeps and awakes, I get no logon screen
Product:	[Plasma] plasmashell	Reporter:	Lee <ALM4-Vendors>
Component:	Screen locking	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	NEEDSINFO WAITINGFORINFO
Severity:	normal	CC:	ALM4-Vendors, kdedev
Priority:	NOR
Version First Reported In:	6.4.5
Target Milestone:	1.0
Platform:	Kubuntu
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Lee 2026-01-02 20:22:26 UTC

Be advised, I'm a Linux and Bugzilla noob.

SUMMARY
On Kubuntu 25.10 With the KDE desktop:
After monitor sleeps and awakes, I get no logon screen.  Instead I get this work around screen:
1)  Press ctrl+alt+F2.
2) In the terminal type "loginctl unlock-session 3".
3) Press ctrl+d.
4) Press ctrl+alt+f1.
Ctrl+alt+f2 does not bring up terminal. So I had to hard power off.

STEPS TO REPRODUCE
1.  Allow monitor to sleep in Kubuntu 25.10 on a HDD or a the Kubuntu 25.10 64bit ISO flashed to a USB thumb drive and booted.
2. Attempt to get back on your desktop.
3.  Try the 4 steps above.
Note: I upgraded KDE so this bug may not affect my system.

OBSERVED RESULT
I did get my login screen after doing step 1 above, but the screen was frozen.

EXPECTED RESULT
Logging back in to my desktop.

SOFTWARE/OS VERSIONS
Windows:  N/A
macOS: N/A
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma:  Kubuntu 25.10
KDE Plasma Version: KDE 6.4.5 (This may have changed when I updated KDE)
KDE Frameworks Version:  6.17.0 (This may have changed when I updated KDE)
Qt Version:  6.9.2

ADDITIONAL INFORMATION
kinfo:
MESA-INTEL: warning: Ivy Bridge Vulkan support is incomplete
Operating System: Kubuntu 25.10
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.2
Kernel Version: 6.17.0-8-generic (64-bit)
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i5-3470 CPU @ 3.20GHz
Memory: 8 GiB of RAM (7.6 GiB usable)
Graphics Processor: Intel® HD Graphics 2500

Comment 1 TraceyC 2026-01-05 18:09:22 UTC

Cut from the Latest Commit field:
Remember, this bug occured on the default KDE version for Kubuntu 25.10.  The KDE version info I submitted probably changed when I updated KDE using a backport source.

Comment 2 TraceyC 2026-01-05 19:20:05 UTC

Can you check get system logs after the bug happens? Reboot your system, cause the bug to happen, and then run this (in TTY if necessary):

  journalctl --boot > ~/log.txt

Then, attach  ~/log.txt to this report. Thanks!