KaOS 2025.09 brings Linux 6.16 kernel, KDE Plasma 6.4, Qt5 removal & enhanced Midna theme

KaOS 2025.09 arrives with upgraded core technology, including the Linux 6.16.9 kernel, KDE Plasma 6.4.5 desktop, KDE Frameworks 6.18.0, and KDE Gear 25.08.1, all built on Qt 6.9.2. The release highlights a fully overhauled Midna theme, featuring new icons, an updated login and splash experience, contemporary window decorations, and a refreshed wallpaper.

Building on these visual changes, KaOS now ships without any Qt5 by default, facilitating a transition to Qt6-only applications after Qt5's end-of-life. KCP, the project’s community packages service, has migrated to Codeberg, further embracing open-source infrastructure.

Alongside these major changes, support has begun for a Plasma-based replacement for the SDDM login manager. The rewritten IsoImageWriter, now QML-based, not only writes ISO files to USB but can also download ISOs from other distributions. System foundations are updated across the board, with new versions of tools like Libxml2, Git, OpenSSL, Bash, and Mesa.

These backend advances are complemented by new software additions such as Typst for markup-based typesetting, Plasma-bigscreen for living room devices, and Hydrogen for drum synthesis. A new Phonon sound backend is active, while SDDM 0.20.0 introduces optional Wayland support. Lastly, Kjournald now offers a graphical log viewer with powerful filtering options.