XFCE4 Brightness Button on Launcher Bar – Increase & Decrease Backlight Manually

First, find out your hardware backlight files

ls /sys/class/backlight/

this should list the device name that controls your backlight

In our case, it is amdgpu_bl0 so we cd into that folder and see the brightness file. Brightness is stored in the file ./amdgpu_bl0/brightess

cat /sys/class/backlight/amdgpu_bl0/brightness

In Arch:

sudo pacman -S acpilight

This gives us xbacklight command ability in XFCE4 without using root

This is a bash shell script to first check whether brightness is going to completely dim the backlight to zero (display off)

# /bin/bash
min_light=$(cat /sys/class/backlight/amdgpu_bl0/brightness)
echo $min_light
if [ "$min_light" -lt 50 ]
then
    echo Too Dim
 else
    sudo xbacklight -dec 10
fi
exit