Issues with Plasma interface

jula

Hello,
I'm quite new using Linux, a few month now and Solus Plasma is my first distribution.

But unfortunately I have a lot of "small" issues that I suspect are related in a way, but I'm not sure, I don't know Linux well enough and I really have no idea on how to start investigating those.

So for now, I'm only able to list the recurrent issues I noticed:

When left clicking on some taskbar icons, they animate but don't show what they are supposed to. This happens quite often.
Examples are launcher menu, some system tray icons like "volume settings", "bluetooth settings", "show hidden icons",...
...and software icons that have multiple windows opened (noticed with Dolphin or Librewolf for example), the windows preview is not showing, nothing happens when clicked. No problem found with single window apps.
When a software crashes, sometimes, it can't be launched again. It always crashes again at launch until I reboot.
Not always the case, but sometimes, I noticed the crash reverts Plasma Renderer Settings to "Software" (without noticing me). Sometimes, but not always, restoring to previous setting helps making the software able to launch again.
A bit too often, KDE Plasma interface crashes, taskbar disappears. It often automatically restarts, but sometimes not. I have to reboot.
Sometimes, I can't wake the computer from sleep mode. I had two cases:
- The login interface doesn't show when pressing any key or moving the mouse. Only the wallpaper and mouse cursor are displayed. No interface to reboot or shutdown.
- Sometimes, it is just a black screen with only the mouse cursor.

For most of these issues, I don't really know what are the conditions that trigger them.

I also have issues with Unreal Engine 5.5 (barely usable):

minute-long freezes
It often (always?) triggers the KDE plasma interface issues I talked about previously
It crashes too frequently
Multiple windows of Unreal Engine doesn't seem to be "recognized" (clicking the taskbar icon maximize/minimize all windows as if it was a single-window software)

(There might be some Unreal Engine specific problems, but I know there are developers using it with other distribution without any major issue, I feel it might be related)

I have no idea where these problems are coming from: Nvidia Drivers? Wayland? KDE plasma? Solus?
Is there anyway to, for example, try launching Unreal Engine using X11?

Any help would be appreciated!

SethStorm666

When I ran Solus - Plasma I had no crashes, but I suspect a combo of Nvidia and wayland might tricker it on your system.
Have you tried logging into X11?

jula

SethStorm666

No I actually have no idea how to do that.
I saw it could be a choice at login in other distributions, but I thought this was not available in Solus.

SethStorm666

jula

At the login screen, lower left corner where it says Wayland, click it.

jula

SethStorm666
It's strange, I just checked, I don't see anything mentioning Wayland on my login screen.
In the lower left corner, the only thing I have is "virtual keyboard".

Harvey

You will not see it because the x11 session is not available by default any more, as explained here https://getsol.us/2025/11/29/solus-4-8-released/#plasma

I do not recommend anyone even bothering to try use X11. Budgie, Gnome and Plasma have all announced support for it is ending soon.

Budgie 10.10 has already dropped X11 (Not available on Solus yet). Gnome 50 is dropping it in March. Plasma 6.8 will drop it and is due in October / late 2026.

jula

Harvey
ok, that's what I thought at first, thank for clarifying that.

I do not really intend to use x11, but I would like to know if wayland might be causing my problems.
I'm not really an advanced user, could this help me investigate?

Harvey

jula

You can try it, if you want. The package required is explained in the blog post I linked plasma-x11.

But Plasma 6.6.1 is a new major release series and is currently in the unstable repo for testing prior to this weeks sync. So you'll get that this Friday/Saturday if you want to wait see if that fixes anything.

jula

Harvey
Great, I can wait, I hope this will help

TraceyC

With the exception of the system tray icons, it sounds like there might be hardware problems.

After you update to Plasma 6.6.1, if you run into the same kinds of issues, try a session with a new user with no customizations and see if the same problems occur.

jula

Thank you, I'll try that if I encounter these issues again.

Here is a quick update:
I feel there is a big overall improvement after the latest update. It's still a bit early to say but I have the impression that some of my issues are gone.
But other ones are still there:
One I already had before but forgot to mention: Alt+Tab window preview is sometime broken. It only displays a empty blurred rectangle area, without the window previews. Alt+Tab functionality works, but it's a blind guess to pick the desired window (encountered only once since the update).

About Unreal Engine: I still have long freeze, but it's a lot better and I now think it might be "normal" as it now only happens when loading never loaded assets.
The main remaining issue is its multiple windows management that still have the same issue: "recognized" as it was only one window (no windows preview when clicking the taskbar icon, it maximize/minimize all windows as it was one). Open windows can only be found using alt+tab or moving them away.
I can try to change way of working to adapt to that behavior, but that is still annoying.

TraceyC

I'm glad to hear that at least some of the issues you saw have been solved with the latest updates.

jula Alt+Tab window preview is sometime broken.

This is something that would need to be reported to the KDE folks through a bug report (if there isn't one already) on the KDE bug tracker . This is a problem with Plasma that Solus can't fix.

The loading times with Unreal is, as you suspect, probably caused by asset loading.

As far as the task manager, a couple of things

It should show windows previews (and I see them on my system) if set to do so. If previews don't show up, check the settings.
The settings also control what clicking an application does

Right click the task manager and click "Configure Icons-only Task Manager" (or Icons-and-Text, depending on which one you have)
"Show small window previews..." needs to be checked to show the previews.
Now click "Behavior" on the left and check what you have set for "Clicking grouped task"

jula

Another update as it seems some issues are still there:

I had a new occurrence of my computer not waking from sleep mode. Only a black screen with the mouse cursor. I had to reboot.
And before that, I also noticed some weird behavior: my computer froze for a short moment, then screens turned black (can't remember for sure if the mouse cursor was visible or not). But everything came back to normal after about a minute. I wasn't doing anything special.

TraceyC

jula I had a new occurrence of my computer not waking from sleep mode. Only a black screen with the mouse cursor. I had to reboot.

If this keeps happening, please file a bug report on the KDE bug tracker , and include some details:

Get the full log (journalctl --user-unit plasma-kwin_wayland --boot 0) from when the screen stays black.
Also, the drm debug log (https://invent.kde.org/plasma/kwin/-/wikis/Debugging/Debugging-DRM-issues) could also be useful

And before that, I also noticed some weird behavior: my computer froze for a short moment, then screens turned black (can't remember for sure if the mouse cursor was visible or not). But everything came back to normal after about a minute. I wasn't doing anything special.

You'll need to report the crash to the KDE bug tracker, in its own report, along with a backtrace.

Open the Crashed Processes Viewer
If there's a related coredump, click on it
Click "Run Interactive Debugger". When it asks, type c to skip paging
At the gdb prompt type "bt"
Copy everything from "Core was generated by..." to the end
Paste that into your bug report on the KDE tracker.

This is a problem with KDE software that Solus can't fix.

Thanks for bringing all these problems up. It may seem like a pain, but reporting these will help them get fixed and make everyone's experience better.

jula

TraceyC Right click the task manager and click "Configure Icons-only Task Manager" (or Icons-and-Text, depending on which one you have)
"Show small window previews..." needs to be checked to show the previews.
Now click "Behavior" on the left and check what you have set for "Clicking grouped task"

Yes, this is my settings. This was not a settings issue, but a behavior that worked half of the time, but really often broke. This seems to have been solved by the update.
Remaining issue only concerns Unreal Engine: only one window is previewed, even if two or more are open. (I feel it is a different issue because preview actually always work and never break anymore, it just does not show all windows as expected).

And yes Unreal used to freeze really randomly before the update, but now it seems to be the case only when loading an asset. This makes sense but it is still a bit slow compared to what I was used to.
(I feel my way of saying it wasn't really clear: it's not my perception that changed, the situation has actually improved and the remaining freeze could be "normal")

jula

TraceyC This is something that would need to be reported to the KDE folks through a bug report (if there isn't one already) on the KDE bug tracker .

Ok, I'll do that, through I'm still not sure if KDE is the relevant level (initially, I thought it could be a problem with Nvidia drivers) and I'm a bit clueless to give any detail.

TraceyC You'll need to report the crash to the KDE bug tracker, in its own report, along with a backtrace.

Open the Crashed Processes Viewer
If there's a related coredump, click on it
Click "Run Interactive Debugger". When it asks, type c to skip paging
At the gdb prompt type "bt"
Copy everything from "Core was generated by..." to the end
Paste that into your bug report on the KDE tracker.

I tried following your instructions. I honestly had no idea what I was doing, but I'll try to do it the next time it happens. Thank you
But I'm not sure there was a "crash", just a black display for a really long time.

Could ibus-ui-tk3 entries in Crashed Processes Viewer be relevant?