Night Shift not working on 2018 Mac Mini with macOS 10.15.2
Have a 2018 mac mini with macOS 10.15.2. The monitor is connected via a Thunderbolt 3 to HDMI cable, and works well. Except for Night Shift. I can enable it, but it isn't working. Moving the slider has no effect. This seems like a pretty significant oversight, or I'm missing something (very likely).
Is there anything I can do to get Night Shift working? I'm using f.lux in the interim, but I'd like the built-in facility for this to work. The monitor is a Dell U2415, if that makes any difference.