Dimming with alt-pgdn is showing circadian response % lowering but the monitor's brightness is still the same.
I am using alt-pagedown to manually adjust the color temperature to lower but the brightness is still the same. I see no effect. I am using 4.118 on Windows 10. This used to work and maybe an update affected it. I already rebooted.
@THenrich I'm having the same issue. I just upgraded to Windows 10 2004 (and also an intel graphic drivers happened after the 2004 rebooted). I cannot go dark with f.lux as I did before. The circadian response from 4% and down doesn't do anything.
Did you solve in the meantime?
Suddenly now works. Don't know why though!