KDE has released Plasma 6.6.5, a maintenance update focused on fixing NVIDIA bugs and other issues before the upcoming KDE Plasma 6.7 release, scheduled for June 16, 2026. This is not a version with significant new visible features, but rather one of those important releases for polishing the daily experience. It includes fixes in KWin, improvements for monitors, adjustments for HDR, Spectacle, accessibility, Discover, Plasma Workspace, and most importantly, a partial solution to recent problems with NVIDIA graphics cards.
KDE itself describes Plasma 6.6.5 as a bug-fix update for KDE Plasma 6. Version 6.6 was released in February 2026, and this revision adds a month’s worth of translations and fixes contributed by the community. KDE emphasizes that the changes are typically small but relevant for the overall stability of the desktop.
KDE Plasma 6.6.5 Solves NVIDIA Graphics Performance Issues and Other Fixes
One of the most significant points is in KWin, KDE Plasma’s window manager and compositor. Plasma 6.6.5 incorporates several fixes related to screen management, multi-GPU configurations, and NVIDIA hardware. The official changelog, for example, mentions a fix to ensure KWin only updates video outputs on GPUs that have actually changed, as well as changes to prevent multi-GPU copies with incompatible formats.
The most delicate problem affects users with the proprietary NVIDIA R595 driver, particularly in configurations with multiple GPUs and external monitors. The Bugzilla report describes a failure with stuttering, periodic freezes, and an avalanche of GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT errors in KWin. The original report mentions an Optimus laptop with an integrated AMD GPU, an NVIDIA GeForce RTX 4070 Laptop, and two external monitors, while other users reported similar cases on CachyOS and with drivers 595.45.04/595.58.03.
The technical explanation is particularly interesting: according to developer Xaver Hugl, the NVIDIA driver could allocate certain linear buffers but not render to them via the OpenGL API. KWin’s multi-GPU copy path would repeatedly attempt to render these buffers, generating errors for every frame when the cursor was visible, and subsequently resorting to a software cursor. Plasma 6.6.5 introduces a check to avoid attempting multi-GPU copies with unsupported formats, thus reducing the problem. Yes, reducing it, not eliminating it. Although the bug is marked as implemented in Plasma 6.6.5, the report is currently reopened, and a comment after the update indicates that the log errors disappear, but some milder stuttering might still be present on certain systems. This means Plasma 6.6.5 appears to significantly improve the problem, but not necessarily eradicate it in all affected scenarios.
Other Improvements Before Version 6.7 Arrives
Another important change is in NVIDIA color handling. The changelog indicates that KWin now sets COLOR_RANGE as full for RGB planes on NVIDIA. This fix may affect color representation in certain display configurations. The color picker has also been corrected to use GL_RGBA instead of GL_RGB, aiming to improve OpenGL ES compatibility.
Plasma 6.6.5 also fixes a detail related to HDR and DDC/CI. The KScreen panel now hides the DDC/CI option when HDR is active. This makes sense because, with HDR content, the system and the display must correctly coordinate brightness, dynamic range, and luminance. Allowing certain external brightness controls could interfere with this behavior. The original text mentions “CI/DCI,” but the correct term in the KDE changelog is DDC/CI. The screenshot utility Spectacle also receives several fixes. These include issues with screenshots not being copied correctly to the clipboard, fixes for the selection editor, the magnifying glass, and window closing when the “exit after export” option is enabled.
Beyond NVIDIA and Spectacle, the changelog shows a quite extensive update. There are fixes in Breeze, Discover, KScreen, KWin, Plasma Desktop, Plasma Workspace, Powerdevil, System Settings, xdg-desktop-portal-kde, and Plasma NetworkManager. Among these, notable corrections include fixes for screen locking, restoration of custom modes after restarting, virtual desktop names not being saved, accessibility in network switches, issues with Klipper, and errors in menus or applets. Plasma 6.6.5 also corrects a problem where shutdown buttons could disappear in launcher menus with systemd 260, as well as periodic freezes on some systems with multiple discrete GPUs.
