Bug 500544

Summary: kwin on wayland: mouse pointer is synchronized or not using hardware cursor.
Product: [Plasma] kwin Reporter: Joao Bueno <gwidion>
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED DOWNSTREAM    
Severity: normal CC: felixonmars, gwidion, johan.claudebreuninger, kokoko3k, kwin-bugs-null, nate, xaver.hugl
Priority: NOR Flags: gwidion: nouveau+
Version First Reported In: 6.2.5   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Bug Depends on: 452117    
Bug Blocks:    

Description Joao Bueno 2025-02-21 19:10:50 UTC 
+++ This bug was initially created as a clone of Bug #452117 +++

(new reporter here - I got the exact same behavior as the O.P.  on bug 452117 

touchpad moves the pointer smoothly around, wireless mouse will behave exactly as
described bellow, to the point of disrupting workflow)


SUMMARY


STEPS TO REPRODUCE
1. 
2. 
3. 

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
SUMMARY
***
There is cursor input lag
***


STEPS TO REPRODUCE
1. In the compositor settings, switch from lowest latency to higher one
2. see that mouse lag changes

You can even try to saturate the gpu use; the mouse will start to stutter too.
Under Xorg, i've regular hardware mouse cursor.



OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
Comment 1 Bug Janitor Service 2025-02-21 19:33:41 UTC 
Thank you for the bug report!

Please note that Plasma 6.2.5 will not be supported for much longer by KDE; supported versions are 5.27., and 6.3 or newer.

Please upgrade to the latest version as soon as your distribution makes it available to you. Plasma is a fast-moving project, and bugs in one version are often fixed in the next one.
Comment 2 Joao Bueno 2025-02-21 19:46:42 UTC 
Wait -

looks like it is a hardware issue on my USB-C -> USB-A adapter  (and therefore multiple mouses misbehaving,
in the same week I changed computers for one with a newer system and Plasma 6.2)

I will wait until the end of the day before closing, though - it is some quite erratic behavior-
(in other news, just now I perceived the "cloned" bug was cloned as "fixed" despite re-asking
questions)

I apologise for the noise.
Comment 3 Nate Graham 2025-02-21 21:37:41 UTC 
No worries!