KWin/X11 is an X11 window manager and a compositing manager. Its primary usage is in conjunction with a Desktop Shell (e.g. KDE Plasma Desktop). KWin/X11 is designed to stay out of the way; users should not notice that they use a window manager at all. Nevertheless KWin/X11 provides a steep learning curve for advanced features, which are available, if they do not conflict with the primary mission. KWin does not have a dedicated targeted user group, but follows the targeted user group of the Desktop Shell using KWin/X11 as it's window manager.
On X11 there is a working implementation for Locally Integrated Menus. Inertial scrolling works too, even under Wine. The scrolling in LibreOffice/Qt is more fluent, and some Chromium functionality, such as drag & drop, is more reliable than on Wayland. Global hotkeys are working for, e.g., push to talk in Telegram and the recording toggle in OBS Studio. Windows get restored at the positions they were closed, especially between different sessions. Applications like games know which screen is the primary one. You can also record your screen in remote desktop applications such as TeamViewer. There are some other minor aspects that just work and lead to an overall pleasant desktop experience.
KWin for X11 was created and for a long time maintained by the KDE developers. Unfortunately, however, the KDE developers decided to abandon X11. In the wake of these events, KWin/X11 has been patched in 2025 by guiodic at guiodic/kwin-x11-improved. The SonicDE project is here to pick up the baton, fix bugs, and make improvements to KWin/X11.
You may want to check out guiodic's Plasma X11 improved guide to get a better Plasma X11 experience. There is also a critical comparison of X11 and Wayland by probonopd.
- a standalone window manager (c.f. openbox, i3) and does not provide any functionality belonging to a Desktop Shell.
- a replacement for window managers designed for use with a specific Desktop Shell (e.g. GNOME Shell)
- a minimalistic window manager
- designed for use without compositing or for X11 network transparency, though both are possible.
We appreciate your interest in contributing! Please refer to the CONTRIBUTING document for everything you need to get started. To report a bug, please use the KWin/X11 bug tracker at Issues · Sonic-DE/kwin-x11-sonic.
We'd love to hear from you on one of our channels. To get end-user support, please also check your distribution's chat or forum.
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