Lab Panel - Modular native StatusNotifier panel

License: This project is licensed under the GPL v2.

Author: JJ Posti - techtimejourney.net - 2026

Lab panel with its alternative blue style.

A lightweight GTK 4/labwc panel with:

• a Python-native org.kde.StatusNotifierWatcher
• tray icons and DBusMenu drop-downs
• a simple labwc/wlroots tasklist using wlrctl
• GTK4 Layer Shell anchoring
• optional user-level systemd support

This panel is intended to replace an external Ayatana/KDE tray watcher. Do not run another StatusNotifier watcher at the same time.

Run directly

python3 lab.py

Choose a style at startup:

LABTRAY_STYLE=Default python3 lab.py
LABTRAY_STYLE=Alternative1 python3 lab.py

Debug tray registration/icons/menus:

LABTRAY_DEBUG=1 python3 lab.py

If a tray applet was already running before the panel started, restart that applet after the panel is running. Some StatusNotifier clients register only once.

Dependencies

Debian / Ubuntu

sudo apt update
sudo apt install \
  python3 \
  python3-gi \
  gir1.2-gtk-4.0 \
  gir1.2-gdkpixbuf-2.0 \
  python3-pydbus \
  dbus-user-session \
  gir1.2-gtk4layershell-1.0 \
  libgtk4-layer-shell0 \
  wlrctl \
  wtype \
  pkg-config

Notes:

• gir1.2-gtk4layershell-1.0 must provide the Gtk4LayerShell GI namespace. The older GTK3 package gir1.2-gtklayershell-0.1 is not enough for this code.
• wlrctl and wtype are used by the tasklist. The tray still starts without them, but the tasklist is hidden or limited.
• Some Ubuntu releases may not ship gir1.2-gtk4layershell-1.0 or wlrctl in the default repositories. Use a backport/PPA, build the missing component, or run on a distro release that packages them.

Build dependencies if you need to build gtk4-layer-shell yourself:

sudo apt install \
  git \
  build-essential \
  meson \
  ninja-build \
  pkg-config \
  gobject-introspection \
  libgtk-4-dev \
  libwayland-dev

Arch Linux

sudo pacman -S \
  python \
  python-gobject \
  gtk4 \
  gtk4-layer-shell \
  python-pydbus \
  dbus \
  wtype \
  pkgconf

Install wlrctl from AUR if you want the tasklist:

yay -S wlrctl

User systemd support

Install the files into ~/.local/share/lab-panel and install user units into ~/.config/systemd/user:

Notice: ./script folder might cause permission denied. Either: bash chmod +x ./scripts/install-user-service.sh OR add bash in front of the command - Like I added to the below.

bash ./scripts/install-user-service.sh

Install and start immediately: Notice: ./script folder might cause permission denied. Either: bash chmod +x ./scripts/install-user-service.sh OR add bash in front of the command - Like I added to the below.

bash ./scripts/install-user-service.sh --enable

Manual service commands:

systemctl --user daemon-reload
systemctl --user enable --now lab-panel.service
systemctl --user status lab-panel.service
journalctl --user -u lab-panel.service -f

If your compositor does not import Wayland session variables into the user manager, run this once from inside the graphical session before starting the service:

systemctl --user import-environment WAYLAND_DISPLAY DISPLAY XDG_CURRENT_DESKTOP XDG_SESSION_TYPE DBUS_SESSION_BUS_ADDRESS XDG_RUNTIME_DIR

Change style with systemctl

The service reads ~/.config/lab-panel/env through EnvironmentFile=. Use the style oneshot units to change the style and restart the panel with a single systemctl command:

systemctl --user start lab-panel-style@Default.service
systemctl --user start lab-panel-style@Alternative1.service

The command updates ~/.config/lab-panel/env and then runs:

systemctl --user try-restart lab-panel.service

You can also edit the file manually:

mkdir -p ~/.config/lab-panel
printf 'LABTRAY_STYLE=Default\n' > ~/.config/lab-panel/env
systemctl --user restart lab-panel.service

Supported styles:

• Default
• Alternative1

Uninstall the user service files: Notice: ./script folder might cause permission denied. Either: bash chmod +x ./scripts/uninstall-user-service.sh OR add bash in front of the command - Like I added to the below.

bash ./scripts/uninstall-user-service.sh

Module layout

lab.py                         small launcher; bootstraps runtime before GTK imports
style.py                       compatibility shim for older imports
lab_panel/runtime.py           environment setup and gtk4-layer-shell LD_PRELOAD re-exec
lab_panel/config.py            constants, supported styles, env flags, debug logger
lab_panel/dbus_helpers.py      session bus and StatusNotifier item canonicalization
lab_panel/native_watcher.py    Python org.kde.StatusNotifierWatcher implementation
lab_panel/tray.py              tray UI, icons, clicks, and DBusMenu rendering
lab_panel/tasklist.py          labwc tasklist backed by wlrctl/wtype
lab_panel/window.py            layer-shell panel window layout
lab_panel/app.py               GTK application and signal handling
lab_panel/style.py             GTK CSS themes
lab_panel/style_command.py     systemd helper for changing LABTRAY_STYLE
systemd/user/*.service         user-level systemd units
scripts/*.sh                   install/uninstall helpers

Troubleshooting

Stop any external watcher before starting this panel:

pkill -f ayatana-indicator || true

If tray icon colors are wrong, try one of the pixmap conversion overrides:

LABTRAY_PIXMAP_FORMAT=bgra python3 lab.py
LABTRAY_PIXMAP_FORMAT=argb python3 lab.py
LABTRAY_PIXMAP_FORMAT=rgba python3 lab.py

For the systemd service, add the variable to ~/.config/lab-panel/env and restart:

printf 'LABTRAY_STYLE=Alternative1\nLABTRAY_DEBUG=1\n' > ~/.config/lab-panel/env
systemctl --user restart lab-panel.service
journalctl --user -u lab-panel.service -f