Bug 442810

Summary:	Erratic mouse wheel scrolling in Firefox
Product:	[Plasma] kwin	Reporter:	Ian Hunter <beanland2>
Component:	input	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	nate
Priority:	NOR
Version First Reported In:	5.22.5
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Ian Hunter 2021-09-22 16:38:55 UTC

SUMMARY

When using Firefox in Plasma/Kwin (X11 and Wayland) scrolling on a page is unpredictable. Scrolling down a few turns of the mouse wheel and stopping makes the page bounce back up to the top and then start scrolling, without mouse input, back down slowly.

STEPS TO REPRODUCE
1. Open Firefox
2. Navigate to a web page with scroll bars (e.g., a Wikipedia entry)
3. Scroll down with the mouse wheel

OBSERVED RESULT


EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch 5.14.6-arch1-1 64 bit
(available in About System)
KDE Plasma Version: 5.22.5
KDE Frameworks Version: 5.86.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
NVIDIA graphics card

May be related to https://bugs.kde.org/show_bug.cgi?id=387797 or https://bugs.kde.org/show_bug.cgi?id=438326

See Bugzilla report here: https://bugzilla.mozilla.org/show_bug.cgi?id=1727091

Comment 1 Nate Graham 2021-09-22 18:29:19 UTC

If it happens on X11 too, then KWin can't be involved, because KWin only processes input events on Wayland. That means it must either be a bug in Libinput (the input driver) or Firefox itself (in how it receives those events).

It's definitely not related to Bug 387797 that only affects Plasma applets using the PlasmaExtras.ScrollArea component. And if it was Bug 438326, then the issue wouldn't happen on X11.