I've created a script that enables you to create custom keyboard shortcuts using the suggested Dell solution for adjusting screen brightness:

https://gist.github.com/lagerone/1568ea6fbb98fd90a3495f9e51e26c8c

You might need to modify it, as the script assumes the laptop screen name is eDP-1. Run xrandr to find out your screen name and modify this line accordingly:

subprocess.run(["xrandr", "--output", "eDP-1", "--brightness", str(adjusted_level)])

Here's the full script:

#!/usr/bin/python3



import logging

import os

import subprocess

import sys

from typing import Literal



logging.basicConfig(level=logging.DEBUG)



FILE_PATH = os.path.join(

    os.path.dirname(os.path.realpath(__file__)), ".screen-brightness"

)





def read_current_level() -> float:

    if not os.path.isfile(FILE_PATH):

        return 1

    with open(

        file=FILE_PATH,

        mode="r",

        encoding="utf-8",

    ) as file:

        current_level = file.readline().strip()

        return float(current_level)





def save_level(level: float) -> None:

    with open(

        file=FILE_PATH,

        mode="w",

        encoding="utf-8",

    ) as file:

        file.write(str(level))





def adjust_level(method: Literal["up", "down"]) -> None:

    adjuster = 0.05 if method == "up" else -0.05

    current_level = read_current_level()

    adjusted_level = current_level + adjuster

    if adjusted_level > 1:

        adjusted_level = 1

    if adjusted_level < 0.2:

        adjusted_level = 0.2

    logging.debug(f"Setting screen brightness to {adjusted_level}.")

    subprocess.run(["xrandr", "--output", "eDP-1", "--brightness", str(adjusted_level)])

    save_level(level=adjusted_level)





if __name__ == "__main__":

    METHOD = sys.argv[1] if len(sys.argv) > 1 else "up"

    adjust_level(method=METHOD)