If I had 'options video acpi_backlight=vendor' to /etc/modprobe.d/options, then the brightness slider still works well but the fn keys for brightness do not work anymore (with an asus laptop).
If I had 'options video acpi_backlight= vendor' to /etc/modprobe. d/options, then the brightness slider still works well but the fn keys for brightness do not work anymore (with an asus laptop).