Bug 506546

Summary: Mouse stops responding to clicks
Product: [Plasma] kwin Reporter: altosch <ales>
Component: compositingAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED NOT A BUG    
Severity: normal CC: ales, anunpretentiousme, kde, xaver.hugl
Priority: NOR    
Version First Reported In: 6.4.1   
Target Milestone: ---   
Platform: Neon   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: kwinrc config file
Output of qdbus org.kde.KWin /KWin supportInformation

Description altosch 2025-07-03 18:37:11 UTC
SUMMARY

The mouse stops responding randomly to clicks.

Suddenly I can't click on anything or just some elements on the screen. Keyboard controls (e.g. ALT+TAB) continue to work. In some cases, disconnecting and reconnecting the mouse helps, sometimes the computer has to be restarted (even repeatedly).

The bug started to occur after updating to Plasma 6.4.1.

STEPS TO REPRODUCE
I've been unable to identify any obvious cause. It's happening randomly.

OBSERVED RESULT
Plasma cannot be controlled with the mouse.

EXPECTED RESULT
The mouse always works.

SOFTWARE/OS VERSIONS

Operating System: KDE neon User Edition
KDE Plasma Version: 6.4.1
KDE Frameworks Version: 6.15.0
Qt Version: 6.9.0
Kernel Version: 6.11.0-29-generic (64-bit)
Graphics Platform: Wayland
Processors: 6 × AMD Ryzen 5 4500U with Radeon Graphics
Memory: 8 GiB of RAM (7,1 GiB usable)
Graphics Processor: AMD Radeon Graphics
Comment 1 altosch 2025-07-03 21:08:58 UTC
To avoid having to reboot, I tried from the console:

kquitapp6 plasmashell && kstart plasmashell

which doesn't work. The mouse is still not working properly.

And then:

kwin_wayland --replace && kstart plasmashell

which works, but some programs get terminated and Firefox crashes every time.

Is there a functional workaround?
Comment 2 David Edmundson 2025-07-04 08:24:33 UTC
Can you also share your ~/.config/kwinrc

---

Next time it happens can you test if ` killall Xwayland`

---

There's a kwin debug console that can be found by typing "kwin" into krunner, if that can find anything useful that would be great.
Comment 3 altosch 2025-07-04 09:13:57 UTC
Created attachment 182937 [details]
kwinrc config file
Comment 4 altosch 2025-07-04 09:46:31 UTC
Thanks for the reply.
I have attached the requested file.

I can't find the kwin debug console. The command “kwin” does nothing.
If I try to use it, I get: Command 'kwin' not found, but can be installed with: sudo apt install kwin-x11.
If I try to install it: kwin-x11 is already the newest version (4:6.4.1-0zneon+24.04+noble+release+build3).

I've also attached the output of the “qdbus org.kde.KWin /KWin supportInformation” command, if that is of any help.

I'll test “killall Xwayland” and let you know.

I have also found that the problem temporarily disappears when I put the laptop to sleep and wake it up again. Fortunately my laptop wakes up very quickly, so as a workaround it's bearable because it doesn't terminate any programs.
Comment 5 altosch 2025-07-04 09:47:17 UTC
Created attachment 182942 [details]
Output of qdbus org.kde.KWin /KWin supportInformation
Comment 6 altosch 2025-07-04 18:24:42 UTC
> Next time it happens can you test if ` killall Xwayland`

No, "killall Xwayland", doesn't work.
Comment 7 David Edmundson 2025-07-04 21:21:02 UTC
When you say mouse, is it a touchpad? 
If you have an external mouse does that work?
Comment 8 altosch 2025-07-05 07:42:05 UTC
(In reply to David Edmundson from comment #7)
> When you say mouse, is it a touchpad? 
> If you have an external mouse does that work?

Neither works. I have a laptop with a touchpad and a mouse attached. When the mouse stops working, the touchpad stops working too.
Sometimes it helps if I unplug the mouse and plug it right back in.

The error also sometimes occurs immediately after the laptop wakes up. I wake it up, the mouse doesn't work: the pointer moves, but I can't click on anything. I put the notebook to sleep and wake it up again, the mouse works.

By the way, the mouse actually seems to work, it's just that Plasma thinks I'm clicking somewhere else. For instance, I want to click on the taskbar, a window closes, etc.
Comment 9 David Edmundson 2025-07-05 07:48:44 UTC
We've got some other reports of this. 

If you can do anything to narrow it down to a specific app that triggers this that would be very helpful.
Comment 10 David Edmundson 2025-07-05 21:57:48 UTC
Do you by any chance run games with Steam Proton Experimental? 
We have a similar bug report that implies a change there could be triggering things.
Comment 11 David Edmundson 2025-07-07 13:56:01 UTC
We have a patch in XWayland for the issue we could reproduce with Proton and have made a request to engineers at Valve. 

If you are able to patch xwayland, you can try this patch https://gitlab.freedesktop.org/zzag/xserver/-/commits/work/zzag/check-flip-empty-winsize. But no worries if not.

I think there's not much else we can do on this ticket, unless you find something else that separates it from the other issue.
Comment 12 altosch 2025-07-08 16:39:14 UTC
Unfortunately, my laptop is a work computer and I can't play games on it.

The good news is that the problem occurs less frequently. In the beginning it was several times an hour. Recently, about twice a day.

So far I have not been able to trace what it might be related to.
Comment 13 altosch 2025-07-12 12:53:42 UTC
I'm starting to suspect it's due to the wireless mouse. I have a regular wireless mouse connected via USB, not bluetooth.
https://support.hp.com/us-en/product/details/dual-mode-mice/28254823

Out of desperation I replaced it with a regular mouse on a wire (same USB port) and for several days the problem did not occur.
I put the wireless mouse back on and right after the first reboot for updates it got stuck again.

Either the mouse is defective, or Plasma has somehow become less tolerant of some signal delay, or something like that.

I'll test it some more and let you know.
Comment 14 anunpretentiousme 2025-07-13 08:11:32 UTC
I confirm that I have been facing this issue too. The mouse is able to move and elements do get highlighted, however they are not clickable. 

I did some investigation and have posted some findings here: https://forums.opensuse.org/t/mouse-clicks-intermittently-stop-working/185920

I also see a similar report on Fedora here: https://discussion.fedoraproject.org/t/fedora-42-kde-bug/154738 

Let me know if there is something I can help with.
Comment 15 altosch 2025-07-21 16:50:20 UTC
In my case it was actually a hardware problem. The error was caused by a broken wireless mouse. When the mouse connects, it probably sends out some confusing signals and so the touchpad is also malfunctioning. 

The fact that the issue started to occur after the Plasma upgrade was probably a coincidence.

I replaced the mouse and everything seems to be fine since. Thanks for the support.
Comment 16 Zamundaaa 2025-07-22 17:47:56 UTC
Thanks for following up on it