| Summary: | Broken scrolling behavior of KDE neon when installed in VirtualBox | ||
|---|---|---|---|
| Product: | [Plasma] kwin | Reporter: | goebbe <christian.goebel> |
| Component: | libinput | Assignee: | KWin default assignee <kwin-bugs-null> |
| Status: | RESOLVED UPSTREAM | ||
| Severity: | normal | CC: | nate |
| Priority: | NOR | ||
| Version First Reported In: | unspecified | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| URL: | https://www.virtualbox.org/ticket/17270 | ||
| Latest Commit: | Version Fixed/Implemented In: | ||
| Sentry Crash Report: | |||
Collecting addidional information on the issue: https://forums.virtualbox.org/viewtopic.php?f=3&t=83614#p431647 It seems libinput *ignores* scroll button events from one device while another device sends movement events, which is the case for mouse integration: the virtual touchpad sends (tons of) movement updates, while the virtual ps/2 mouse scrollwheel sends button events. With mouse integration disabled, both events are sent by the same virtual ps/2 mouse. Most notably, both libinput-debug-events and xev receive events correctly in all cases. This explains why the first workaround (disabling VirtualBox mouse integration) works. The following points to another workaround: https://superuser.com/questions/1270811/inconsistent-and-erratic-mouse-wheel-in-linux-while-moving-the-mouse-pointer Second workaround - as decribed on superuser.com: Replace libinput by xf86-input-evdev in combination with imwheel I hope this helps. Seems like a libinput bug. Please report upstream at https://gitlab.freedesktop.org/libinput/libinput/-/issues/. Thanks! This is a reference to the three year old bug report on Virtualbox: https://www.virtualbox.org/ticket/17270 ... and a two year old bug report for xf86-input-libinput: https://gitlab.freedesktop.org/xorg/driver/xf86-input-libinput/-/issues/9 |
SUMMARY When installed inside a VirtualBox, the scrolling behavior in the KDE-environment ist broken. Scrolling is interrupted as soon as the mouse pointer moves, which gives a very inconsistent an frustrating scrolling behavior. STEPS TO REPRODUCE 1. Install KDE-Neo inside a VirtualBox (e.g. on Ubuntu 20.04) 2. Open e.g. Discover and try to scroll down the list of updates OBSERVED RESULT Scrolling does not work as it should. Actually it is pretty hard to scroll without moving the mouse at all. EXPECTED RESULT Smooth scrolling - like an install outside of VirtualBox SOFTWARE/OS VERSIONS Linux/KDE Plasma: KDE neon 5.20 installed in VirtualBox on Ubuntu 20.04 (available in About System) KDE Plasma Version: 5.20.1 KDE Frameworks Version: 5.75.0 Qt Version: 5.15.0 Workaround: Disable the VirtualBox mouse integration via Xinput. The following worked for me: ~$ xinput ⎡ Virtual core pointer id=2 [master pointer (3)] ⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)] ⎜ ↳ VirtualBox mouse integration id=9 [slave pointer (2)] ⎜ ↳ ImExPS/2 Generic Explorer Mouse id=11 [slave pointer (2)] ⎣ Virtual core keyboard id=3 [master keyboard (2)] ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)] ↳ Power Button id=6 [slave keyboard (3)] ↳ Sleep Button id=7 [slave keyboard (3)] ↳ Video Bus id=8 [slave keyboard (3)] ↳ AT Translated Set 2 keyboard id=10 [slave keyboard (3)] ~$ xinput disable 9 ADDITIONAL INFORMATION I had the same experience with older versions of KDE neon, VirtualBox and Ubuntu - so it seems that the problem is not due to a recent regression. Xfce offers a options in the mouse-setting that allows to disables VirtualBox mouse integration (permanently) - which offers an accessible way to fix the bad scrolling experience when installed inside a VirtualBox. The problem seems to be related to VirtualBox mouse integration, and should/could probably fixed there. :-( It would be great is there would be an (GUI) option to disable it. Please feel free to move the bug report to another component. I had a hard time to decide if this is the correct place (Kwin, libinput) to report the bug. Keep up the great work.