Plasma panels disappear after screen turns off due to inactivity

borisbsc · 2025-02-26 12:56:56

For many months in Plasma 5 and 6, my system tray panel in the bottom-right (set to autohide) would not reappear after the screen turned off due to inactivity and then back on. The only workaround was to quickly enter and exit edit mode which made it visible again. The main application panel at the bottom center (also set to autohide) worked without issues.

Recently after upgrading to Plasma 6.3 both panels disappear after the screen turns off and back on. Entering and exiting edit mode no longer restores them. The only way to bring them back is to use "Manage Desktop and Panels" to remove them completely and then add the default Plasma panel. But even the default panel without any position customizations vanishes after the screen turns off and back on.

I use an external screen on a laptop, with the laptop display disabled. Plasma is 6.3.1 on Wayland.

How can I fix this?

seth · 2025-02-26 16:00:39

Try to disable the kscreen daemon.
(What likely happens is that the output unregisters, kscreen changes the output geometry, plasma responds to the zero-sized root window and your panel bites the dust)

borisbsc · 2025-02-26 18:33:38

Hmm, interesting. The "KScreen 2" background service was already disabled and not running. I don't remember ever disabling it or anything.
When I started it my display arrangement settings got reset immediately, but the disappearing panel issue doesn't seem to be happening anymore. I'll wait a few days just to be sure though.
If KScreen is responsible for screen settings, how did everything work when it was disabled all this time (arranging displays, changing display modes, display mode persistence, etc.)?

V1del · 2025-02-26 20:04:09

I'm fairly certain you can't actually disable kscreen on a wayland session and/or it simply gets DBUS invoked on an as needed basis by kwin.

That said I can't repro... Is this a multi GPU system and the dedicated screen connected to a dGPU?

seth · 2025-02-26 20:42:08

after the screen turned off due to inactivity and then back on

Whether the output unregisters on DPMS is output specific.
The more the terms "hdmi", "Tv", "dock" and "adapter" describe your output, the more likely this will happen.

And then there's oc.

When I started it my display arrangement settings got reset immediately, but the disappearing panel issue doesn't seem to be happening anymore.

https://wiki.archlinux.org/title/KDE#Un … lution_set

borisbsc · 2025-02-27 01:55:57

I guess I spoke too soon, it's still happening.

Before when I enabled and started KScreen 2 I tested it with an on-demand turn off and the panel was there so it appeared solved, but now when it got turned off due to actual inactivity the panel was gone.

The more the terms "hdmi", "Tv", "dock" and "adapter" describe your output, the more likely this will happen.

The display is connected via USB-C/USB-C which I think uses DP alt mode under the hood, so no adapters and such.

Is this a multi GPU system and the dedicated screen connected to a dGPU?

No, the external display is on iGPU. The laptop has a Ryzen 7840HS (using oss amdgpu) and an RTX4070 (using proprietary nvidia). On this laptop only HDMI is hard wired to the dGPU. In fact it doesn't even have a mux switch (or it's faulty from day 1), as switching to the dGPU turns off the builtin display completely and without an external screen you can't even switch back (as you can't see the BIOS screen). But advanced optimus does work so I keep it in hybrid mode all the time.

If it means anything, when the panel is gone if I press the Super key the Application Launcher is shown in the middle of the screen and not its usual place bottom-left. Also, I keep the panel's visibility as Dodge Windows so it gets auto-hidden when a window is maximized.

Last edited by borisbsc (2025-02-27 01:58:16)

seth · 2025-02-27 08:06:33

Check the system journal resp. https://wiki.archlinux.org/title/Core_d … _core_dump whether anything crashes and or plasma withdraws panels or otherwise throws a fit over a zero sized output.
Also check your plasma (applet) configuration whether you maybe now have a bazillion micro-panels, https://bugs.kde.org/show_bug.cgi?id=490732

Arch Linux

#1 2025-02-26 12:56:56

Plasma panels disappear after screen turns off due to inactivity

#2 2025-02-26 16:00:39

Re: Plasma panels disappear after screen turns off due to inactivity

#3 2025-02-26 18:33:38

Re: Plasma panels disappear after screen turns off due to inactivity

#4 2025-02-26 20:04:09

Re: Plasma panels disappear after screen turns off due to inactivity

#5 2025-02-26 20:42:08

Re: Plasma panels disappear after screen turns off due to inactivity

#6 2025-02-27 01:55:57

Re: Plasma panels disappear after screen turns off due to inactivity

#7 2025-02-27 08:06:33

Re: Plasma panels disappear after screen turns off due to inactivity

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