Bug 168875 - qt gui scrollbar scrolling is slow and unresponsive
Summary: qt gui scrollbar scrolling is slow and unresponsive
Status: RESOLVED DUPLICATE of bug 152911
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: graphics stack (show other bugs)
Version:
(earliest affected)
25.2.6.2 release
Hardware: All Linux (All)
: medium normal
Assignee: Not Assigned
URL:
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Keywords:
Depends on:
Blocks:
 
Reported: 2025-10-15 20:17 UTC by sunwebrw
Modified: 2025-10-15 20:43 UTC (History)
2 users (show)

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Description sunwebrw 2025-10-15 20:17:31 UTC
Libreoffice scrolling with scrollbar is broken for qt5, qt6 and kf6 VCL plugins.

I'm using Plasma desktop with Wayland. I've tried to enable/disable hardware acceleration and smooth scolling with no result.

Comparison:
Calligrawords(fully Qt) - scrolling is super fast and precise

LibreOffice - qt5, qt6 and kf6 - grab scrollbar with a mouse and move it up and down. The result, sometimes choppy scrolling and sometimes after scrollbar changed position and it's either catching up or after some time instantly scroll to the new place. It's unusable. I've noticed that qt5 is a bit better but maybe it was my imagination.

LibreOffice - gtk4 - it's way better than qt variants however still pretty choppy and laggy.

LibreOffice - gtk3 - by far the best version. It doesn't feel as smooth and precise as Calligrawords but it's very close.

Video demonstration - https://youtu.be/wlFdm6Fu8h8
Comment 1 Julien Nabet 2025-10-15 20:33:46 UTC
It's a bit expected Calligra works very well on qt since it's developed for KDE.

About gtk4, implementation of it in LO is in progress.
For qt rendering, there's been lots of work made on 25.8 branch.

On which Linux distrib are you? Perhaps you may give a try to a 25.8 version?
Eg: on Debian testing, there's LO 25.8.1.1 available on Debian repo.
Comment 2 Michael Weghorn 2025-10-15 20:43:35 UTC
(In reply to sunwebrw from comment #0)
> I'm using Plasma desktop with Wayland.

That sounds like tdf#152911 then, should significantly improve with Qt 6.11 (or a Qt version with the relevant Qt wayland changes backported).

*** This bug has been marked as a duplicate of bug 152911 ***