Plasma 5: historical notes on desktop customization

Source and license: this article includes material compiled and adapted from Tips and Optimizations from My Experience with KDE Plasma 5 by 斬風千雪 (風雪城). The original and the portions of this article adapted from it are available under CC BY-NC-SA 4.0, which requires attribution, noncommercial use, and sharing under the same license. This article selects material from the original, adjusts its wording, and adds version and verification boundaries; the original author's personal experiences remain attributable to that author. This license notice was added on 2026-10-09. It applies only to the source material identified above and its adaptations, does not extend that license to other content on this site, and does not imply the original author's endorsement of this site.

This is a curated clipping with explicit version boundaries, drawn from a technical article on Fengxuecheng. It preserves configuration ideas and pointers to tools; historical faults and workarounds are included only to explain the environment at the time, not as general installation advice today. All first-person experiences below refer to the original author; this site has not reproduced those faults.

Version#

The original environment was Plasma 5.26.2; references to the "latest" version must not be read as referring to the current release. In particular, X11 tools, older KWin effects, and Plasma 6 / Wayland interfaces are not directly interchangeable.

File pickers#

Compared with GNOME, KDE's file pickers could be described as a hundred flowers blooming and a hundred schools of thought contending: there are all sorts of pickers, along with all sorts of bugs. This section records how those issues were addressed.
✳️ Qt6
The Qt 6 file picker was extraordinarily sluggish on the original author's KDE setup. Affected applications included Telegram Desktop, OBS, and Dolphin Emulator. The picker responded only about once every half minute and did not follow the system theme. In that situation, the Qt 5 file-picker backend of XDG desktop portal could be used instead.
After installation, prefix the application's desktop-file Exec= line with /usr/bin/env QT_QPA_PLATFORMTHEME=xdgdesktopportal. Alternatively, put export QT_QPA_PLATFORMTHEME="xdgdesktopportal" in an environment profile to apply it globally, which also affects other Qt 5 file pickers.
🦊 Firefox
In about:config, change widget.use-xdg-desktop-portal.file-picker to 1 to use the XDG desktop portal file picker.
You can also follow the original author's configuration and enable all the related options for a more consistent appearance.
🎨 Kvantum compatibility
After the changes above, add xdg-desktop-portal-kde,xdg-desktop-portal,xdg-document-portal to Kvantum's excluded-window list. Otherwise, the file picker becomes translucent, which looks awkward when the background is dimmed.
🐞 Bugs after a KDE Plasma update
After updating to KDE Plasma 5.26, the original author encountered a bug where the Qt 5 file picker took about half a minute to open and could also crash the application. Following the solution in this thread, the author fixed that particular issue by recreating the QtProject configuration. First exit the relevant applications, back up the configuration, and reproduce the problem; do not treat deleting these two files as a universal step for every Portal failure.
Additionally, KDE Plasma 5.26.2 caused the XDG desktop portal file picker to revert to the default Breeze theme, making it look out of place. Adding /usr/bin/killall xdg-desktop-portal-kde to autostart was the original article's workaround for that specific version. After upgrading, check whether it is still needed rather than blindly carrying it forward.

Background blur#

The following xprop approach uses X11 window properties and does not apply to native Wayland windows. KWin effects are also constrained by plugin ABI and version compatibility.
🪟 Enable it for an individual window
Use xprop -f _KDE_NET_WM_BLUR_BEHIND_REGION 32c -set _KDE_NET_WM_BLUR_BEHIND_REGION 0 to enable background blur for a selected window.
🔧 Use a plugin
Download and enable the Force Blur script under System Settings - Window Management - KWin Scripts. Add the windows you want blurred to enable the effect automatically for those windows.
If your computer is powerful enough, consider the second mode, the whitelist mode. It forces blur on all windows outside the whitelist; on slower hardware this may cause KWin to drop frames.

Black windows and desktop freezes#

After KDE Plasma 5.26, notifications or windows would often turn completely black, followed by the entire desktop environment freezing. In this situation, you can bind killall kwin_x11 && kwin_x11 --replace &, which fully terminates and restarts KWin, to a keyboard shortcut. When warning signs appear, such as menus and notifications turning black or Latte Dock flickering, press the shortcut promptly to restart it.
The following is the original article's X11 recovery record. Forcibly terminating the window manager interrupts work, so save your content and verify the process first. It does not apply to Wayland sessions. If the desktop has already frozen, press shortcuts such as Ctrl+S or F12 to save unsaved work; some keyboard shortcuts may still work at this point. Then switch to tty2 and run kill -KILL "$(ps -e | grep kwin_x11 | awk -F' ' '{print $1}')". Switch back to tty1, the graphical environment, and run kwin_x11 --replace &.

Rounded corners#

GNOME has a heavily modified third-party window manager, mutter-rounded, that implements rounded corners at the window-manager level very smoothly. KDE can approximate rounded corners through window decorations, but the result is imperfect and can show the "Korners" bug: square gray shadow corners. The LightlyShaders desktop effect, however, can produce rounded corners similar to macOS.
The LightlyShaders repository is at https://github.com/a-parhom/LightlyShaders; follow its README to install it.
LightlyShaders currently has two branches: master and v2.0.
The master branch is for KWin 5.25.5 and earlier. It works by "painting" rounded corners over windows, which uses more resources, though not as excessively as the README suggests; Intel Iris graphics can run it smoothly. The rounded corners drawn by the master branch are crisp and smooth, already close to macOS.
The v2.0 branch was completely rewritten using features introduced in 5.25.90, so it does not work with older KWin versions. It has much lower overhead, but still has bugs that need later updates. The v2.0 branch also requires a compatible window decoration, such as SierraBreezeEnhanced.
Choose the branch that matches your KWin version.
You can customize the excluded windows in lightlyshaders.cpp. Consider adding Wine applications and particularly unusual windows, such as NetEase Cloud Music's desktop lyrics.

Invoking shortcut actions from commands#

The qdbus command can invoke shortcut actions in Qt applications, including KDE. You can use it in scripts for quick KDE configuration or combine it with other programs.
Qt QDBusViewer shows the shortcut actions available in each program.
For example, the shortcut command to show the desktop grid is qdbus org.kde.kglobalaccel /component/kwin invokeShortcut ShowDesktopGrid.

Dark mode#

The Plasma 5 environment in the original article used custom switching between light and dark themes; this does not describe the capabilities of later versions. If a theme has both light and dark variants installed, switching is much easier.
For quick switching, write a script to toggle dark mode with one action. You still have to change the wallpaper yourself, though!
This script requires Python and PyQt5 to be installed.
https://github.com/YidaozhanYa/kde-dark-mode

fcitx5 integration#

In newer versions, fcitx5 can use the KDE Plasma theme for a more consistent appearance.
Under Configure Addons - Classic User Interface, change the theme to KDE Plasma.

Redirecting configuration files#

KDEHOME is a mechanism from the KDE4 era. The original article's export KDEHOME="${XDG_CONFIG_HOME}/.kde4" is retained only as a record of an older software path; it is not a general method for redirecting Plasma 5/6 configuration. For modern programs, check their XDG configuration paths.

A more capable calendar clock#

The Event Calendar widget can replace the default digital clock.
Event Calendar supports a single-line display, offers many configuration options and shortcut actions, and can also show the weather.

A media player in the top panel#

KDE Plasma's built-in media-player widget does not work particularly well in a single-row top panel, especially when right-aligned. A third-party media-player widget can replace it.
Place Media Controller Plus, also called Media Player in the Add Widgets interface, alongside Current Playing.
If you dislike the No media text, you can modify the source of Current Playing. See the original author's modified version at https://github.com/YidaozhanYa/kde-currently-playing-custom.

Better animations#

Nonlinear animations can replace some of the default linear ones.
Maximize Kinetic can replace Maximize Animation
Minimize Kinetic or Scale OutExpo can replace Minimize Animation (Shrink)
Fading Popups Kinetic can replace Dialog Fade Transition
Open/Close Kinetic can replace Window Open/Close Fade Animation
You can also install Slide tooltips to animate tooltips, the hints shown when hovering the mouse.