Bug 504239

Summary: Duplicate cursor appears after mouse is idle for a couple seconds, with single display or if multiple monitors using different resolutions are connected; display is set to Prefer color accuracy or with refresh rate > 120Hz
Product: [Plasma] kwin Reporter: kdebugrtackingsystem.oyrus
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: adamska156, andres.hung, bpadhy01, bugsbe.dramatic182, equeim, jlp, jmsaunders, john.kizer, julien.dlq, kanerbw, kdedev, linus, xaver.hugl
Priority: NOR Keywords: multiscreen
Version First Reported In: 6.1.4   
Target Milestone: ---   
Platform: openSUSE   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=505708
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Picture of the issue.
Image showing duplicate cursor and corruption on the lower half of the display

Description kdebugrtackingsystem.oyrus 2025-05-14 21:44:25 UTC
Created attachment 181309 [details]
Picture of the issue.

SUMMARY
When using two monitors with different resolutions (1080p (no VRR, no HDR) and 1440p (VRR + HDR)), another mouse cursor appears to the right of the real cursor after being idle for a couple of seconds. Moving the mouse removes the fake cursor immediately.

STEPS TO REPRODUCE
1. Have two monitors with different resolutions.
2. Move the cursor to the window with higher resolution and stop moving it for a couple of seconds.

OBSERVED RESULT
Another cursor appears to the right of the real cursor.

EXPECTED RESULT
Nothing happens.

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20250513
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.9.0
Kernel Version: 6.14.6-1-default (64-bit)
Graphics Platform: Wayland
Processors: 16 × 11th Gen Intel® Core™ i7-11700 @ 2.50GHz
Memory: 31.1 GiB of RAM
Graphics Processor 1: AMD Radeon RX 7900 XT
Graphics Processor 2: llvmpipe
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7D09
System Version: 1.0

ADDITIONAL INFORMATION
The second cursor is not visible in screenshots or screen captures. The time it takes for the second cursor to appear seems to have some variance. When trying to record the issue with GPU Screen Recorder, the second cursor did not appear at all. Using Spectacle, the second cursor appeared on screen but was not recorded. Disconnecting the second monitor removes the issue and reconnecting it reintroduces it.
Comment 1 Bug Janitor Service 2025-05-14 22:33:38 UTC Comment hidden (spam)
Comment 2 kdebugrtackingsystem.oyrus 2025-05-15 04:03:41 UTC Comment hidden (spam)
Comment 3 Vlad Zahorodnii 2025-05-15 06:57:12 UTC
Do you know if the monitors are connected to different GPUs? If you set KWIN_FORCE_SW_CURSOR=1 environment variable, is the issue reproducible?
Comment 4 kdebugrtackingsystem.oyrus 2025-05-15 18:25:49 UTC
(In reply to Vlad Zahorodnii from comment #3)
> Do you know if the monitors are connected to different GPUs? If you set
> KWIN_FORCE_SW_CURSOR=1 environment variable, is the issue reproducible?

Both monitors are physically connected to the discrete GPU. Adding the environmental variable (as an executable .sh file to ~/.config/plasma-workspace/env/) and rebooting fixes the issue. Removing the variable and rebooting makes the issue reproducible again. The issue started after I updated the OS. I noticed that alongside many other updates, KDE Frameworks was updated to 6.14.0 and Linux kernel to 6.14.6.
Comment 5 John Kizer 2025-05-19 04:43:03 UTC
Hi - you mentioned the monitors having different resolutions, so just to double-check - does the issue occur if you artificially set the higher-res monitor to a resolution that matches the lower-res one?

Thanks!
Comment 6 kdebugrtackingsystem.oyrus 2025-05-19 19:07:24 UTC
(In reply to John Kizer from comment #5)
> Hi - you mentioned the monitors having different resolutions, so just to
> double-check - does the issue occur if you artificially set the higher-res
> monitor to a resolution that matches the lower-res one?
> 
> Thanks!

Yes, setting the same resolution to both monitors fixes the issue.
Comment 7 John Kizer 2025-05-20 00:08:34 UTC
Thanks!
Comment 8 TraceyC 2025-05-28 21:11:11 UTC
*** Bug 504885 has been marked as a duplicate of this bug. ***
Comment 9 TraceyC 2025-05-28 21:18:31 UTC
(In reply to kdebugrtackingsystem.oyrus from comment #0)

Something that was noticed in the duplicate report was that this setting caused the bug:
Display Configuration -> Color accuracy: Prefer efficiency

Can you confirm that the bug is not seen with "Prefer color accuracy", and then seen again when switching to "Prefer efficiency"?
Thanks.
Comment 10 kanerbw 2025-05-29 01:36:18 UTC
(In reply to TraceyC from comment #9)
> (In reply to kdebugrtackingsystem.oyrus from comment #0)
> 
> Something that was noticed in the duplicate report was that this setting
> caused the bug:
> Display Configuration -> Color accuracy: Prefer efficiency
> 
> Can you confirm that the bug is not seen with "Prefer color accuracy", and
> then seen again when switching to "Prefer efficiency"?
> Thanks.

Actually, the bug happened with "Prefer color accuracy." It didn't happen with "Prefer efficiency."
Comment 11 kdebugrtackingsystem.oyrus 2025-05-29 17:59:15 UTC
(In reply to TraceyC from comment #9)
> (In reply to kdebugrtackingsystem.oyrus from comment #0)
> 
> Something that was noticed in the duplicate report was that this setting
> caused the bug:
> Display Configuration -> Color accuracy: Prefer efficiency
> 
> Can you confirm that the bug is not seen with "Prefer color accuracy", and
> then seen again when switching to "Prefer efficiency"?
> Thanks.

For me, that setting has no effect on the issue. Setting the same resolution to both monitors or forcing software cursor fixes the issue for me.
Comment 12 Barunes Padhy 2025-05-30 16:20:48 UTC
(In reply to kanerbw from comment #10)
> (In reply to TraceyC from comment #9)
> > (In reply to kdebugrtackingsystem.oyrus from comment #0)
> > 
> > Something that was noticed in the duplicate report was that this setting
> > caused the bug:
> > Display Configuration -> Color accuracy: Prefer efficiency
> > 
> > Can you confirm that the bug is not seen with "Prefer color accuracy", and
> > then seen again when switching to "Prefer efficiency"?
> > Thanks.
> 
> Actually, the bug happened with "Prefer color accuracy." It didn't happen
> with "Prefer efficiency."

Actually this is what that solved for me too! selecting “Prefer efficiency” over “Prefer color accuracy” solves this issue. I only have a singular monitor.

I will paste my output of "inxi -SGaz":

System:
  Kernel: 6.14.6-1-default arch: x86_64 bits: 64 compiler: gcc v: 14.2.1
    clocksource: tsc avail: hpet,acpi_pm
    parameters: BOOT_IMAGE=/boot/vmlinuz-6.14.6-1-default
    root=UUID=f753194c-dbad-44c6-8636-be0769ff0a04 splash=silent
    resume=/dev/disk/by-uuid/4720645c-e75c-4a59-8a24-9cebfb58d85e quiet
    security=apparmor psi=1 mitigations=auto
  Desktop: KDE Plasma v: 6.3.5 tk: Qt v: N/A info: frameworks v: 6.14.0
    wm: kwin_wayland tools: avail: xscreensaver vt: 3 dm: 1: GDM v: 48.0 2: SDDM
    note: stopped Distro: openSUSE Tumbleweed 20250522
Graphics:
  Device-1: Advanced Micro Devices [AMD/ATI] Navi 32 [Radeon RX 7700 XT /
    7800 XT] vendor: Tul / PowerColor driver: amdgpu v: kernel arch: RDNA-3
    code: Navi-3x process: TSMC n5 (5nm) built: 2022+ pcie: gen: 4
    speed: 16 GT/s lanes: 16 ports: active: DP-1 empty: DP-2, DP-3, HDMI-A-1,
    Writeback-1 bus-ID: 03:00.0 chip-ID: 1002:747e class-ID: 0300
  Device-2: Advanced Micro Devices [AMD/ATI] Raphael vendor: Gigabyte
    driver: amdgpu v: kernel arch: RDNA-2 code: Navi-2x process: TSMC n7 (7nm)
    built: 2020-22 pcie: gen: 4 speed: 16 GT/s lanes: 16 ports: active: none
    empty: DP-4, DP-5, DP-6, HDMI-A-2, Writeback-2 bus-ID: 13:00.0
    chip-ID: 1002:164e class-ID: 0300 temp: 36.0 C
  Device-3: Logitech Webcam C270 driver: snd-usb-audio,uvcvideo type: USB
    rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 7-1.3:4
    chip-ID: 046d:0825 class-ID: 0102 serial: <filter>
  Display: wayland server: X.org v: 1.21.1.15 with: Xwayland v: 24.1.6
    compositor: kwin_wayland driver: X: loaded: modesetting unloaded: vesa
    alternate: fbdev dri: radeonsi gpu: amdgpu display-ID: 0
  Monitor-1: DP-1 model: LG (GoldStar) ULTRAGEAR serial: <filter>
    built: 2024 res: mode: 2560x1440 hz: 180 scale: 100% (1) dpi: 93 gamma: 1.2
    size: 697x392mm (27.44x15.43") diag: 800mm (31.5") ratio: 16:9 modes:
    max: 2560x1440 min: 640x480
  API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
    device: 1 drv: radeonsi device: 2 drv: swrast gbm: drv: radeonsi
    surfaceless: drv: radeonsi wayland: drv: radeonsi x11: drv: radeonsi
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 25.1.1 glx-v: 1.4
    direct-render: yes renderer: AMD Radeon RX 7800 XT (radeonsi navi32 LLVM
    20.1.4 DRM 3.61 6.14.6-1-default) device-ID: 1002:747e memory: 15.62 GiB
    unified: no display-ID: :1.0
  API: Vulkan v: 1.4.309 layers: 6 device: 0 type: discrete-gpu name: AMD
    Radeon RX 7800 XT (RADV NAVI32) driver: N/A device-ID: 1002:747e
    surfaces: xcb,xlib,wayland device: 1 type: integrated-gpu name: AMD
    Radeon Graphics (RADV RAPHAEL_MENDOCINO) driver: N/A device-ID: 1002:164e
    surfaces: xcb,xlib,wayland device: 2 type: cpu name: llvmpipe (LLVM
    20.1.4 256 bits) driver: N/A device-ID: 10005:0000
    surfaces: xcb,xlib,wayland
  Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
    de: kscreen-console,kscreen-doctor wl: wayland-info
    x11: xdpyinfo, xprop, xrandr
Comment 13 bugsbe.dramatic182 2025-06-01 16:36:55 UTC
Hi, just wanted to add to this bug. I'm experiencing this bug. I'm on openSUSE TW and I have a single monitor. It appears for me regardless if Color accuracy is set to "Prefer efficiency" or "Prefer color accuracy".  But, what does make it disappear however is if I lower my refresh rate from my native 144hz to 120hz.

I'll paste my output of "inxi -SGaz" like the previous user did:
System:
  Kernel: 6.14.6-1-default arch: x86_64 bits: 64 compiler: gcc v: 14.2.1
    clocksource: tsc avail: hpet,acpi_pm
    parameters: BOOT_IMAGE=/vmlinuz-6.14.6-1-default
    root=/dev/mapper/linux-root splash=silent quiet security=selinux
    selinux=1 amdgpu.ppfeaturemask=0xffffffff mitigations=auto
  Desktop: KDE Plasma v: 6.3.5 tk: Qt v: N/A info: frameworks v: 6.14.0
    wm: kwin_wayland with: krunner vt: 1 dm: SDDM Distro: openSUSE Tumbleweed
    20250522
Graphics:
  Device-1: Advanced Micro Devices [AMD/ATI] Navi 32 [Radeon RX 7700 XT /
    7800 XT] vendor: Tul / PowerColor driver: amdgpu v: kernel arch: RDNA-3
    code: Navi-3x process: TSMC n5 (5nm) built: 2022+ pcie: gen: 4
    speed: 16 GT/s lanes: 16 ports: active: DP-3 empty: DP-1, DP-2, HDMI-A-1,
    Writeback-1 bus-ID: 28:00.0 chip-ID: 1002:747e class-ID: 0300
  Device-2: Logitech Brio 500 driver: hid-generic,usbhid,uvcvideo type: USB
    rev: 2.1 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 3-1.4:5
    chip-ID: 046d:0943 class-ID: 0300 serial: <filter>
  Display: wayland server: X.org v: 1.21.1.15 with: Xwayland v: 24.1.6
    compositor: kwin_wayland driver: X: loaded: modesetting unloaded: fbdev,vesa
    dri: radeonsi gpu: amdgpu display-ID: 0
  Monitor-1: DP-3 model: AOC U34G2G4R3 serial: <filter> built: 2020 res:
    mode: 3440x1440 hz: 120 scale: 100% (1) dpi: 110 gamma: 1.2
    size: 797x334mm (31.38x13.15") diag: 864mm (34") modes: max: 3440x1440
    min: 720x400
  API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
    device: 1 drv: swrast gbm: drv: zink surfaceless: drv: radeonsi wayland:
    drv: radeonsi x11: drv: radeonsi
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 25.1.1 glx-v: 1.4
    direct-render: yes renderer: AMD Radeon RX 7800 XT (radeonsi navi32 LLVM
    20.1.4 DRM 3.61 6.14.6-1-default) device-ID: 1002:747e memory: 15.62 GiB
    unified: no display-ID: :0.0
  API: Vulkan v: 1.4.309 layers: 8 device: 0 type: discrete-gpu name: AMD
    Radeon RX 7800 XT (RADV NAVI32) driver: N/A device-ID: 1002:747e
    surfaces: xcb,xlib,wayland device: 1 type: cpu name: llvmpipe (LLVM
    20.1.4 256 bits) driver: N/A device-ID: 10005:0000
    surfaces: xcb,xlib,wayland
  Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
    de: kscreen-console,kscreen-doctor gpu: lact wl: wayland-info
    x11: xdpyinfo, xprop, xrandr
Comment 14 kanerbw 2025-06-04 00:07:28 UTC
FYI, this bug seems to be resolved for me with the latest openSUSE TW release
Comment 15 TraceyC 2025-06-04 14:15:35 UTC
(In reply to kanerbw from comment #14)
> FYI, this bug seems to be resolved for me with the latest openSUSE TW release

That's great to hear.

(In reply to kdebugrtackingsystem.oyrus from comment #0)
Are you still seeing the duplicate cursor after running updates (with “Prefer color accuracy”)?

Is anyone else seeing this after updates?
Comment 16 kdebugrtackingsystem.oyrus 2025-06-04 17:44:29 UTC
Created attachment 182030 [details]
Image showing duplicate cursor and corruption on the lower half of the display
Comment 17 kdebugrtackingsystem.oyrus 2025-06-04 17:46:55 UTC
(In reply to TraceyC from comment #15)
> (In reply to kanerbw from comment #14)
> > FYI, this bug seems to be resolved for me with the latest openSUSE TW release
> 
> That's great to hear.
> 
> (In reply to kdebugrtackingsystem.oyrus from comment #0)
> Are you still seeing the duplicate cursor after running updates (with
> “Prefer color accuracy”)?
> 
> Is anyone else seeing this after updates?

Yes, I still have the original issue. In addition, after updating my TW, the lower half of the main display gets corrupted whenever the second cursor appears. Please see the attached image above.
Comment 18 TraceyC 2025-06-05 15:36:21 UTC
Well, bummer. Thanks for the additional details.
Comment 19 equeim 2025-06-10 19:07:15 UTC
I have the same issue on Tumbleweed with Radeon 7900 GRE and two monitors.

1080p monitor is connected via HDMI, and arranged to the left. 1440p one is connected over DisplayPort and is arranged to the right. 1440p also supports HDR which is enabled and supports VRR which is disabled (IDK if this is related).

Color accuracy is set to "Prefer efficiency" for both monitors.

Additionally, duplicate cursor only appears on the right (1440p) monitor.
Comment 20 equeim 2025-06-10 19:09:41 UTC
(In reply to equeim from comment #19)
> I have the same issue on Tumbleweed with Radeon 7900 GRE and two monitors.
> 
> 1080p monitor is connected via HDMI, and arranged to the left. 1440p one is
> connected over DisplayPort and is arranged to the right. 1440p also supports
> HDR which is enabled and supports VRR which is disabled (IDK if this is
> related).
> 
> Color accuracy is set to "Prefer efficiency" for both monitors.
> 
> Additionally, duplicate cursor only appears on the right (1440p) monitor.

1440p monitor is also set to 120 Hz (although it supports 144 Hz). 1080p monitor is 60 Hz.

1080p - Dell S2340L
1440p - Gigabyte G27Q
Comment 21 equeim 2025-06-11 21:11:06 UTC
(In reply to equeim from comment #20)
> (In reply to equeim from comment #19)
> > I have the same issue on Tumbleweed with Radeon 7900 GRE and two monitors.
> > 
> > 1080p monitor is connected via HDMI, and arranged to the left. 1440p one is
> > connected over DisplayPort and is arranged to the right. 1440p also supports
> > HDR which is enabled and supports VRR which is disabled (IDK if this is
> > related).
> > 
> > Color accuracy is set to "Prefer efficiency" for both monitors.
> > 
> > Additionally, duplicate cursor only appears on the right (1440p) monitor.
> 
> 1440p monitor is also set to 120 Hz (although it supports 144 Hz). 1080p
> monitor is 60 Hz.
> 
> 1080p - Dell S2340L
> 1440p - Gigabyte G27Q

The issue also disappears if I set the 1440p monitor to 60 Hz (but keep the native resolution).
Comment 22 adamska156 2025-06-12 06:06:26 UTC
(In reply to equeim from comment #21)
> (In reply to equeim from comment #20)
> > (In reply to equeim from comment #19)
> > > I have the same issue on Tumbleweed with Radeon 7900 GRE and two monitors.
> > > 
> > > 1080p monitor is connected via HDMI, and arranged to the left. 1440p one is
> > > connected over DisplayPort and is arranged to the right. 1440p also supports
> > > HDR which is enabled and supports VRR which is disabled (IDK if this is
> > > related).
> > > 
> > > Color accuracy is set to "Prefer efficiency" for both monitors.
> > > 
> > > Additionally, duplicate cursor only appears on the right (1440p) monitor.
> > 
> > 1440p monitor is also set to 120 Hz (although it supports 144 Hz). 1080p
> > monitor is 60 Hz.
> > 
> > 1080p - Dell S2340L
> > 1440p - Gigabyte G27Q
> 
> The issue also disappears if I set the 1440p monitor to 60 Hz (but keep the
> native resolution).

I have virtually the exact same setup as you (GPU, monitor specs, and orientation) and I have the same experience troubleshooting it, what works and doesn't work. Issue only ever appears on the main monitor (1440p 144fps). Disabling second monitor (1080p 60fps) fixes the issue as does lowering main monitor to match slower monitor's 60fps refresh rate. I also get the screen corruption everywhere below wherever the double mouse cursor is visible.
Comment 23 equeim 2025-06-12 12:12:44 UTC
Enabling Adaptive Sync also makes the issue go away, though it also makes Plasma animations stutter occasionally (but that may be a placebo effect).
Comment 24 TraceyC 2025-06-13 19:09:55 UTC
I'm setting this to confirmed, since at least two people with similar hardware are able to currently reproduce the bug
Comment 25 kanerbw 2025-06-19 09:31:25 UTC
FYI, this bug was temporarily resolved for me, but with the latest from OpenSUSE TW, I get the mouse and the screen artifacting error when using two monitors. The KWIN_FORCE_SW_CURSOR=1 workaround doesn't resolve it. 

Should the Severity be updated to at least Major since the only workarounds are to not use one of my two monitors or to lower the refresh rate of one of them from 144hz to 60hz?
Comment 26 Linus Lotz 2025-06-19 10:39:40 UTC
I also have this problem. I have a single 240 Hz monitor. It is less apparent when using a lower refresh rate (at 60 Hz I don't see the duplicate cursor but I see some flickering corruption around it, which is smaller than at higher refresh rates). I tried without success:
- switching between "Prefer efficiency" and "Prefer color accuracy"
- switching HDR on and off

What also seems to fix it is to enable Adaptive sync, but that causes flicker on my monitor so I'd like to keep it off (maybe that improves with kwin changes for plasma 6.4).

My "inxi -SGaz" output:
System:
  Kernel: 6.15.2-zen1 arch: x86_64 bits: 64 compiler: gcc v: 14.2.1
    clocksource: tsc avail: hpet,acpi_pm
    parameters: initrd=\EFI\nixos\3qp5cps5iwrs8hlf73k8n4dxdrg52wvk-initrd-linux-zen-6.15.2-initrd.efi
    init=/nix/store/0chjdyi3kjxwnqjzr7xa9lxljcbvn2b4-nixos-system-linus-desktop-25.11pre816272.9e83b64f727c/init
    quiet splash boot.shell_on_fail loglevel=3 rd.systemd.show_status=false
    rd.udev.log_level=3 udev.log_priority=3 splash loglevel=0
    lsm=landlock,yama,bpf
  Desktop: KDE Plasma v: 6.3.5 tk: Qt v: N/A info: frameworks v: 6.14.0
    wm: kwin_wayland vt: 2 dm: SDDM Distro: NixOS 25.11 (Xantusia)
Graphics:
  Device-1: Advanced Micro Devices [AMD/ATI] Navi 31 [Radeon RX 7900 XT/7900
    XTX/7900 GRE/7900M] driver: amdgpu v: kernel arch: RDNA-3 code: Navi-3x
    process: TSMC n5 (5nm) built: 2022+ pcie: gen: 4 speed: 16 GT/s lanes: 16
    ports: active: DP-1 empty: DP-2, DP-3, HDMI-A-1, Writeback-1
    bus-ID: 03:00.0 chip-ID: 1002:744c class-ID: 0300
  Device-2: Logitech HD Webcam B910 driver: snd-usb-audio,uvcvideo type: USB
    rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 5-4.2.3:9
    chip-ID: 046d:0823 class-ID: 0e02 serial: <filter>
  Display: wayland server: Xwayland v: 24.1.6 compositor: kwin_wayland
    driver: gpu: amdgpu display-ID: 0
  Monitor-1: DP-1 model: Gigabyte AORUS FO32U2P serial: <filter> built: 2024
    res: 3840x2160 dpi: 141 gamma: 1.2 size: 699x395mm (27.52x15.55")
    diag: 793mm (31.2") ratio: 16:9 modes: max: 3840x2160 min: 720x400
  API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
    device: 1 drv: swrast gbm: drv: kms_swrast surfaceless: drv: radeonsi
    wayland: drv: radeonsi x11: drv: radeonsi
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 25.1.3 glx-v: 1.4
    direct-render: yes renderer: AMD Radeon RX 7900 XT (radeonsi navi31 LLVM
    19.1.7 DRM 3.63 6.15.2-zen1) device-ID: 1002:744c memory: 19.53 GiB
    unified: no display-ID: :0.0
  Info: Tools: api: clinfo, eglinfo, glxinfo
    de: kscreen-console,kscreen-doctor gpu: corectrl
Comment 27 TraceyC 2025-06-19 16:15:20 UTC
(In reply to kanerbw from comment #25)
> Should the Severity be updated to at least Major since the only workarounds
> are to not use one of my two monitors or to lower the refresh rate of one of
> them from 144hz to 60hz?

The severity is correct at Normal to my thinking, and here's why. This is a cosmetic issue that does not affect functionality, which would normally make it Minor. Also, there is a workaround that isn't too difficult, just annoying (lowering the refresh rate).

As background, this describes how we generally set Severity (the lower case part of Importance)
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging#Set_the_Severity_field
Comment 28 Andres Hung 2025-06-20 16:19:37 UTC
Adding a comment to say I've also been experiencing this issue, and that changing the Color accuracy setting from "Prefer color accuracy" to "Prefer efficiency" fixed it. Saw it in 6.3.5 as well as 6.4.0. Only using a single display @144Hz.

inxi -SGaz output:

System:
  Kernel: 6.12.34 arch: x86_64 bits: 64 compiler: gcc v: 14.3.0
    clocksource: tsc avail: hpet,acpi_pm
    parameters: BOOT_IMAGE=(hd0,gpt1)//kernels/wshpcrckw2rr89rjq5jrliapi6xqsy2c-linux-6.12.34-bzImage
    init=/nix/store/w9bfqiyjbdcpnay90ap8fm0qkb2bf55m-nixos-system-AHNIX-25.11.20250619.08f2208/init
    loglevel=4 lsm=landlock,yama,bpf
  Desktop: KDE Plasma v: 6.4.0 tk: Qt v: N/A info: frameworks v: 6.15.0
    wm: kwin_wayland vt: 2 dm: SDDM Distro: NixOS 25.11 (Xantusia)
Graphics:
  Device-1: Advanced Micro Devices [AMD/ATI] Navi 31 [Radeon RX 7900 XT/7900
    XTX/7900 GRE/7900M] vendor: Tul / PowerColor driver: amdgpu v: kernel
    arch: RDNA-3 code: Navi-3x process: TSMC n5 (5nm) built: 2022+ pcie:
    gen: 4 speed: 16 GT/s lanes: 16 ports: active: DP-2 empty: DP-1, DP-3,
    HDMI-A-1, Writeback-1 bus-ID: 03:00.0 chip-ID: 1002:744c class-ID: 0300
  Device-2: Advanced Micro Devices [AMD/ATI] Raphael vendor: ASUSTeK
    driver: amdgpu v: kernel arch: RDNA-2 code: Navi-2x process: TSMC n7 (7nm)
    built: 2020-22 pcie: gen: 4 speed: 16 GT/s lanes: 16 ports: active: none
    empty: DP-4,HDMI-A-2,Writeback-2 bus-ID: 0e:00.0 chip-ID: 1002:164e
    class-ID: 0300 temp: 39.0 C
  Display: wayland server: Xwayland v: 24.1.8 compositor: kwin_wayland
    driver: gpu: amdgpu display-ID: 0
  Monitor-1: DP-2 model: LG (GoldStar) ULTRAGEAR serial: <filter>
    built: 2023 res: 2560x1440 dpi: 109 gamma: 1.2 size: 597x336mm (23.5x13.23")
    diag: 685mm (27") ratio: 16:9 modes: max: 2560x1440 min: 640x480
  API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
    device: 1 drv: radeonsi device: 2 drv: swrast gbm: drv: radeonsi
    surfaceless: drv: radeonsi wayland: drv: radeonsi x11: drv: radeonsi
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 25.1.4 glx-v: 1.4
    direct-render: yes renderer: AMD Radeon RX 7900 XT (radeonsi navi31 LLVM
    19.1.7 DRM 3.61 6.12.34) device-ID: 1002:744c memory: 19.53 GiB
    unified: no display-ID: :0.0
  Info: Tools: api: eglinfo,glxinfo de: kscreen-console,kscreen-doctor
Comment 29 Julien Delquié 2025-06-20 17:44:47 UTC
Same issue here.
Changing "Prefer efficiency” and “Prefer color accuracy" does not change anything.
Changing "Adaptive sync" seems to remove screen corruption but does not remove duplicate mouse.
Lowering refresh rate from 240 Hz to 144 Hz (and without adaptive sync, and with Prefer efficiency) seams to be a workaround for my setup.
Thus, I didn’t tried KWIN_FORCE_SW_CURSOR=1 workaround.

$ inxi -SGaz
System:
  Kernel: 6.15.2-gentoo-dist arch: x86_64 bits: 64 compiler: gcc v: 15.1.0
    clocksource: tsc avail: hpet,acpi_pm
    parameters: BOOT_IMAGE=/kernel-6.15.2-gentoo-dist
    root=UUID=f6337320-71f4-4af6-81ad-3826e3f04f5c ro
    resume=UUID=f6337320-71f4-4af6-81ad-3826e3f04f5c resume_offset=80250880
    acpi_enforce_resources=lax quiet loglevel=0 rd.systemd.show_status=false
    systemd.show_status=false udev.log_priority=0 vt.global_cursor_default=0
    delayacct splash
  Desktop: KDE Plasma v: 6.4.0 tk: Qt v: N/A wm: kwin_wayland dm: SDDM
    Distro: Gentoo Base System release 2.17
Graphics:
  Device-1: Advanced Micro Devices [AMD/ATI] Navi 32 [Radeon RX 7700 XT /
    7800 XT] vendor: ASUSTeK driver: amdgpu v: kernel arch: RDNA-3
    code: Navi-3x process: TSMC n5 (5nm) built: 2022+ pcie: gen: 4
    speed: 16 GT/s lanes: 16 ports: active: DP-2,HDMI-A-1
    empty: DP-1,DP-3,Writeback-1 bus-ID: 03:00.0 chip-ID: 1002:747e
    class-ID: 0300
  Display: unspecified server: X.Org v: 24.1.8 with: Xwayland v: 24.1.8
    compositor: kwin_wayland driver: X: loaded: amdgpu
    unloaded: modesetting,radeon alternate: fbdev,vesa dri: radeonsi
    gpu: amdgpu display-ID: :0 screens: 1
  Screen-1: 0 s-res: 3840x1080 s-dpi: 96 s-size: 1016x285mm (40.00x11.22")
    s-diag: 1055mm (41.54")
  Monitor-1: DP-2 pos: primary,right model: VG249QM1A serial: <filter>
    built: 2023 res: mode: 1920x1080 hz: 240 scale: 100% (1) dpi: 93 gamma: 1.2
    size: 527x296mm (20.75x11.65") diag: 604mm (23.8") ratio: 16:9 modes:
    max: 1920x1080 min: 720x400
  Monitor-2: HDMI-A-1 pos: left model: VZ249 serial: <filter> built: 2019
    res: mode: 1920x1080 hz: 60 scale: 100% (1) dpi: 93 gamma: 1.2
    size: 527x296mm (20.75x11.65") diag: 604mm (23.8") ratio: 16:9 modes:
    max: 1920x1080 min: 720x400
  API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
    device: 1 drv: swrast gbm: drv: radeonsi surfaceless: drv: radeonsi x11:
    drv: radeonsi inactive: wayland
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 25.1.4 glx-v: 1.4
    direct-render: yes renderer: AMD Radeon RX 7800 XT (radeonsi navi32 LLVM
    20.1.7 DRM 3.63 6.15.2-gentoo-dist) device-ID: 1002:747e memory: 15.62 GiB
    unified: no
  API: Vulkan v: 1.4.313 layers: 5 device: 0 type: discrete-gpu name: AMD
    Radeon RX 7800 XT (RADV NAVI32) driver: mesa radv v: 25.1.4
    device-ID: 1002:747e surfaces: N/A
  Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
    de: kscreen-console,kscreen-doctor gpu: amdgpu_top wl: wayland-info
    x11: xdpyinfo, xprop, xrandr
Comment 30 Julien Delquié 2025-06-20 18:12:40 UTC
This issue also happen on wayland version of SDDM.
Comment 31 Jordan 2025-06-22 00:09:27 UTC
I'm seeing this issue on a 7600 XT with a 4k@240hz monitor in KDE 6.4.0.

I reproed the issue in Gnome so I think it's most likely a driver issue.
Comment 32 kdebugrtackingsystem.oyrus 2025-06-22 05:31:32 UTC
(In reply to Jordan from comment #31)
> I'm seeing this issue on a 7600 XT with a 4k@240hz monitor in KDE 6.4.0.
> 
> I reproed the issue in Gnome so I think it's most likely a driver issue.

I do not have the same issue with Fedora Silverblue.
Comment 33 Jordan 2025-06-22 05:50:54 UTC
(In reply to kdebugrtackingsystem.oyrus from comment #32)
> (In reply to Jordan from comment #31)
> > I'm seeing this issue on a 7600 XT with a 4k@240hz monitor in KDE 6.4.0.
> > 
> > I reproed the issue in Gnome so I think it's most likely a driver issue.
> 
> I do not have the same issue with Fedora Silverblue.

I am on OpenSUSE Tumbleweed with everything up to date.
Comment 35 Linus Lotz 2025-06-25 11:34:19 UTC
I no longer see this problem after updating the linux firmware.
Comment 36 Zamundaaa 2025-06-25 13:12:56 UTC
Yeah, it's that driver bug.