Brightness control does not work for Adder WS

[digital-idiot]

OS=Manjaro
DE=KDE
Device=Adder WS

When I run system76-oled from terminal I get the following error:

INFO  system76_oled] Vendor 'System76' Model 'addw1' has OLED display on 'eDP-1'
thread 'main' panicked at 'failed to connect to D-Bus session bus: D-Bus error: Using X11 for dbus-daemon autolaunch was disabled at compile time, set your DBUS_SESSION_BUS_ADDRESS instead (org.freedesktop.DBus.Error.NotSupported)', src/libcore/result.rs:1188:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.