kdedimmer

A click-through screen dimmer overlay for KDE Plasma Wayland. Adds a transparent dark layer on top of everything (including panels and fullscreen apps) with adjustable opacity.

Features

• Covers all monitors with dark overlay
• Fully click-through (doesn't intercept mouse/keyboard)
• Always on top (above panels, fullscreen apps, everything)
• System tray icon with slider control
• D-Bus interface for CLI control
• Systemd user service for autostart

Dependencies

• Qt 6 (Widgets, Gui, DBus, WaylandClient)
• KF6 StatusNotifierItem
• layer-shell-qt
• wayland-client

Arch Linux:

sudo pacman -S qt6-base qt6-wayland layer-shell-qt wayland kstatusnotifieritem

Debian/Ubuntu:

sudo apt install qt6-base-dev qt6-base-private-dev qt6-wayland-dev liblayershellqtinterface-dev libkf6statusnotifieritem-dev libwayland-dev cmake

Installation

From AUR (Arch Linux)

yay -S kdedimmer
# or
paru -S kdedimmer

Then enable the service:

systemctl --user enable --now kdedimmer

From Source

./install.sh

This will:

1. Build the project
2. Install binary to ~/.local/bin/
3. Install systemd user service
4. Enable and start the service

Usage

System Tray

• Left-click tray icon for slider popup (0-90% opacity)
• Scroll wheel over tray icon to adjust (up = less dim, down = more dim)
• Right-click for menu (toggle, quit)
• Middle-click to toggle on/off

CLI Commands

kdedimmer              # Start daemon (if not using systemd)
kdedimmer +5           # Increase opacity by 5%
kdedimmer -5           # Decrease opacity by 5%
kdedimmer set 50       # Set opacity to 50%
kdedimmer toggle       # Toggle on/off
kdedimmer on           # Enable overlay
kdedimmer off          # Disable overlay
kdedimmer get          # Print current opacity
kdedimmer status       # Print running status

Keyboard Shortcuts

Add custom shortcuts in KDE Settings → Shortcuts → Custom Shortcuts:

Action	Command
Dim more	kdedimmer +5
Dim less	kdedimmer -5
Toggle dimmer	kdedimmer toggle

Service Management

systemctl --user status kdedimmer   # Check status
systemctl --user restart kdedimmer  # Restart
systemctl --user stop kdedimmer     # Stop
systemctl --user disable kdedimmer  # Disable autostart

Uninstall

systemctl --user disable --now kdedimmer
rm ~/.local/bin/kdedimmer
rm ~/.config/systemd/user/kdedimmer.service
systemctl --user daemon-reload

Technical Details

• Uses layer-shell-qt with LayerOverlay to render above all windows
• Empty Wayland input region for complete click-through
• D-Bus service: org.kde.kdedimmer at path /Dimmer

License

GPL-3.0-or-later