Using night shift/f.lux on external monitors Mac OS 10.15 I’m having an issue using Night Shift, f.lux, or any blue light filter application on 2 of the 3 external monitors I have hooked up to my MacBook Pro via a Dell docking station. This is my hardware:


MacBook Pro 2019 
Dell D6000 dock
Dell 24 in monitor
Dell 24 in monitor
LG 34 in monitor 


I’ve tried reseating cables, reinstalling display link drivers, and downloading other blue light filter applications like f.lux.
I have a Dell D6000 docking station and had the same issue.
Got it working after I did the following:

Quit the Displaylink Manager application and set it so that it does not start on startup.
Unplug the Dock connection to your Macbook.
Replug the Dock connection to your Macbook.

The monitors should work AND with Night Shift without needing to have the DisplayLink manager running in the background.