Does this issue still happen?

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https://bugs.launchpad.net/bugs/1782177

Title:
  Screen sometimes jumps to full brightness on resume from suspend

Status in Linux:
  Won't Fix
Status in linux package in Ubuntu:
  Incomplete

Bug description:
  At night, I usually turn my brightness down as far as it will go using
  the brightness keys. This makes it dim, but visible and not off. When
  I walk away for a while, the screen goes to sleep, and when I come
  back and move the mouse, the screen jumps to full brightness, which is
  very unpleasant at night. Investigating, it seems that the brightness
  in intel_backlight is getting reset to 4437, but the one in
  acpi_video0 reads 0.

      $ for file in brightness max_brightness actual_brightness;
      > do
      >   for directory in /sys/class/backlight/intel_backlight/ 
/sys/class/backlight/acpi_video0/
      > do
      > echo $directory$file : $(cat $directory$file)
      > done
      > done
      /sys/class/backlight/intel_backlight/brightness : 4437
      /sys/class/backlight/acpi_video0/brightness : 0
      /sys/class/backlight/intel_backlight/max_brightness : 4437
      /sys/class/backlight/acpi_video0/max_brightness : 15
      /sys/class/backlight/intel_backlight/actual_brightness : 4437
      /sys/class/backlight/acpi_video0/actual_brightness : 0

  After I press the button to increase the brightness one notch, they
  are back in sync, and then I can turn it back down as well.

      $ for file in brightness max_brightness actual_brightness;
      >  do
      >    for directory in /sys/class/backlight/intel_backlight/ 
/sys/class/backlight/acpi_video0/
      >  do
      >  echo $directory$file : $(cat $directory$file)
      >  done
      >  done
      /sys/class/backlight/intel_backlight/brightness : 53
      /sys/class/backlight/acpi_video0/brightness : 1
      /sys/class/backlight/intel_backlight/max_brightness : 4437
      /sys/class/backlight/acpi_video0/max_brightness : 15
      /sys/class/backlight/intel_backlight/actual_brightness : 53
      /sys/class/backlight/acpi_video0/actual_brightness : 1

  This is on a fresh install of xubuntu 18.04. Seems like a regression
  from 16.04, which I ran on the same laptop without this issue.

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