Allow night light to be configured per display
Feature summary
Currently, night light is applied to all displays. It would be great if you could configure it per-display that it can be disabled for some displays. For example, I use my HDMI port to play video on my TV and don't want night light applied to it.
How would you like it to work
In the display settings panel, remove the Night Light tab and move its settings into the display-specific settings in the main displays panel. Add a checkbox that says "Apply nightlight settings to all displays" which defaults to enabled, which will apply the settings to other displays for people who want it enabled across all displays.
If "Apply nightlight settings to all displays" is not enabled, then each display will have its own individual values for the nightlight settings. If it is disabled then changing a nightlight setting in any display will update the settings for all other displays.
Relevant links, screenshots, screencasts etc.
I'm not sure how difficult it would be to control the color for each display independently but I know redshift could do it with the option:
[randr]
screen=0
crtc=0,1