I recently moved to using Kubuntu 26.04 after being on windows for quite a few years - it’s been fine but there’s something wrong with using the mouse on external monitor that is capped at 60hz as compared to my laptop screen which has a refresh rate of 240hz.
The cursor on my monitor feels laggy and not so smooth. On the laptop screen, the cursor is laggy when set to 60hz but when i change it to 120hz or 240hz the cursor feels smooth. The same behaviour is observed with the touchpad.
What I’ve done so far (with the help of an AI):
Research suggests GNOME/Mutter handles hardware cursor plane initialisation more reliably than KWin on Wayland, resulting in better perceived cursor smoothness at 60Hz. Is this a known KWin limitation, and are there any KWin-specific settings or workarounds to improve cursor plane handling on external monitors connected via Thunderbolt dock?
Hardware info:
Operating System: Kubuntu 26.04 LTS
KDE Plasma Version: 6.6.4
KDE Frameworks Version: 6.24.0
Qt Version: 6.10.2
Kernel Version: 7.0.0-15-generic (64-bit)
Graphics Platform: Wayland
Processors: 24 × Intel® Core™ Ultra 9 275HX
Memory: 96 GiB of RAM (93.7 GiB usable)
Graphics Processor 1: Intel® Graphics
Graphics Processor 2: NVIDIA GeForce RTX 5060 Laptop GPU
Docking station: Dell Thunderbolt 5 SD25TB5
Monitor: Lenovo L32p-30 (60hz max)
I’ll appreciate any suggestions. Thanks.
The cursor on my monitor feels laggy and not so smooth. On the laptop screen, the cursor is laggy when set to 60hz but when i change it to 120hz or 240hz the cursor feels smooth. The same behaviour is observed with the touchpad.
What I’ve done so far (with the help of an AI):
- Mouse polling rate confirmed active at ~1000Hz via libinput debug-events
- usbhid.mousepoll=1 kernel parameter applied and confirmed via /sys/module/usbhid/parameters/mousepoll
- Acceleration profile set to flat (PointerAccelerationProfile=1 in ~/.config/kcminputrc)
- Hardware cursor confirmed active — no software cursor fallback in journalctl
- KWin LatencyPolicy=Low set in ~/.config/kwinrc — no noticeable difference
- Cursor feels perfectly smooth on the laptop’s built-in 240Hz display, noticeably less smooth on 60Hz external monitors
Research suggests GNOME/Mutter handles hardware cursor plane initialisation more reliably than KWin on Wayland, resulting in better perceived cursor smoothness at 60Hz. Is this a known KWin limitation, and are there any KWin-specific settings or workarounds to improve cursor plane handling on external monitors connected via Thunderbolt dock?
Hardware info:
Operating System: Kubuntu 26.04 LTS
KDE Plasma Version: 6.6.4
KDE Frameworks Version: 6.24.0
Qt Version: 6.10.2
Kernel Version: 7.0.0-15-generic (64-bit)
Graphics Platform: Wayland
Processors: 24 × Intel® Core™ Ultra 9 275HX
Memory: 96 GiB of RAM (93.7 GiB usable)
Graphics Processor 1: Intel® Graphics
Graphics Processor 2: NVIDIA GeForce RTX 5060 Laptop GPU
Docking station: Dell Thunderbolt 5 SD25TB5
Monitor: Lenovo L32p-30 (60hz max)
I’ll appreciate any suggestions. Thanks.