On Ubuntu 24 based KDE Neon (today updated all packages and reboot - 6.17.0-29-generic) I am seeing some “journalctl -xef” log entries which looks like a issue. I was checking the logs, because my screen does not turn off after the screen is automatically password locked due to inactivity.
May 24 17:45:21 .. org_kde_powerdevil[2040]: Native interface revision mismatch (requested 1 / available 2) for interface QWaylandApplication
May 24 17:45:23 .. wireplumber[1679]: WpSiStandardLink:0x5c656d1eb490 1 of 1 PipeWire links failed to activate
May 24 17:45:23 .. wireplumber[1679]: WpSiStandardLink:0x5c656cebad20 1 of 1 PipeWire links failed to activate
May 24 17:45:23 .. wireplumber[1679]: WpSiStandardLink:0x5c656d1331a0 1 of 1 PipeWire links failed to activate
May 24 17:47:24 .. wireplumber[1679]: WpSiNode:0x5c656d0f10c0 Object activation aborted: proxy destroyed
May 24 17:47:24 .. wireplumber[1679]: WpSiNode:0x5c656d0f10c0 failed to activate item: Object activation aborted: proxy destroyed
System Settings > Power Management > Energy Saving
“Turn off screen” 80 seconds, “When locked: 10 seconds”
System Settings > Screen Locking
“Lock screen automatically”: 1 minute
“Delay before password required”: 5 seconds
Setting “Turn off screen” to 55 seconds, does not fix it (screen does not turn off, even in the past it was turning off on Neon).
$ systemd-inhibit --list|grep -E “WHAT|block”
WHO UID USER PID COMM WHAT WHY MODE
PowerDevil 1000 user 2040 org_kde_powerde handle-power-key:handle-suspend-key:handle-hibernate-key:handle-lid-switch KDE handles power events block
$ cat ~/.config/powerdevilrc
[AC][Display]
DimDisplayIdleTimeoutSec=-1
DimDisplayWhenIdle=false
TurnOffDisplayIdleTimeoutSec=60
TurnOffDisplayIdleTimeoutWhenLockedSec=10
[AC][SuspendAndShutdown]
AutoSuspendAction=0
Operating System: KDE neon User Edition
KDE Plasma Version: 6.6.5
KDE Frameworks Version: 6.26.0
Qt Version: 6.11.1
Kernel Version: 6.17.0-29-generic (64-bit)
Graphics Platform: Wayland