https://bugs.kde.org/show_bug.cgi?id=526876
William Varmus <[email protected]> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |[email protected] --- Comment #1 from William Varmus <[email protected]> --- This is a Qt 6.12 Wayland regression, not a KDE bug. A physical mouse wheel can be reported through a device marked with `PixelScroll`, causing Qt's shared `QTabBar` implementation to take the pixel-scrolling path instead of switching tabs. This affects Qt applications using the standard tab bar, including Dolphin, Konsole, and Kate. The local fix is one condition in `src/widgets/widgets/qtabbar.cpp`: ``` - if (event->device()->capabilities().testFlag( - QInputDevice::Capability::PixelScroll)) { + if (event->device()->capabilities().testFlag( + QInputDevice::Capability::PixelScroll) + && event->source() != Qt::MouseEventNotSynthesized) { ``` Physical mouse-wheel events then use QTabBar's existing discrete tab-switching path, while synthesized touchpad events keep pixel scrolling. This is a shared Qt fix, not an application-specific Dolphin patch. It preserves the input-device capabilities and touchpad behavior. The proposed upstream workaround [Gerrit 778943](https://codereview.qt-project.org/c/qt/qtbase/+/778943) instead removes `PixelScroll` from the Wayland touchpad device globally. I use Arch Linux and built a local `qt6-base 6.12.0-2` with this change and verified that it restores mouse-wheel tab switching in Dolphin, Konsole and other KDE apps. The complete Arch packaging recipe is available at [qt6-base-tabbar-wheel-fix](https://github.com/willvar/qt6-base-tabbar-wheel-fix). Arch users need a patched `qt6-base`; rebuilding Dolphin, Konsole, or Kate will not help. As a temporary workaround or diagnostic, an affected application can be launched through XWayland with `QT_QPA_PLATFORM=xcb dolphin`. -- You are receiving this mail because: You are watching all bug changes.
