[e-users] backlight issue

Hi
I meet backlight issue with enlightenment X session and nvidia driver.
First thing to know: this happens with other WM (xfce)
conditions:
PC (not laptop)
"nvidia quadro 600 pro" graphic card
X session
linux kernels lts and/or last 4.18.16 kernel
efl-git enlightenment-git
nvidia-390xx-dkms driver
Backlight setting doesn't work inside e or any wm. I tried everything,
no solution.
But good news xrandr works for me

https://wiki.archlinux.org/title/Backlight#Xorg:_adjust_perceived_brightness_with_xrandr
This works:
xrandr --output output_name --brightness 2

For me, it's a temporary solution. I don't understand what happens...
Greetings
--
Maderios