KDE Plasma 6.6.6 lands as the final maintenance release for the 6.6 branch, delivering a focused set of bug fixes that address real daily-driver pain points. Chief among them is a fix for a clipboard issue that could cause XWayland apps to lag or freeze entirely after locking the screen, a problem that would have bitten anyone running legacy X11 applications under a Wayland session. A security patch also hardens the ksystemstats Intel helper against path traversal, and the Task Manager widget now guards against maliciously crafted .desktop files.
KWin picks up several stability improvements in this release. A crash triggered when apps opened dialogs in non-standard ways has been resolved, along with a startup failure that could hit systems with older GPUs and drivers. A memory leak caused by using window rules to force decorations on Firefox is also gone. On the Wayland portal side, xdg-desktop-portal-kde now prevents clipboard deadlocks when transfers fail and correctly restores full-workspace screencast sessions. Discover, KDE's software center, fixes a bug where reviews appeared multiple times and tightens up accessibility action handling.
Since Plasma 6.7 shipped on 2026-06-16 with per-screen virtual desktops, the new Union theming system, and combined ICC and HDR support, this release is squarely aimed at users on rolling or stable distributions that still track the 6.6 branch. With no further 6.6 updates planned, the path forward is 6.7 and its own growing bugfix cadence.
