Redshift might be good, but why can't I customize more than that?

I mean, can I write my own ICC profile, and use here?

There is also Redshift / Night light, but why not turning it on at all times?

Comments

[Valts Liepiņš]

This seems like an Ubuntu specific feature and most likely it is customizable.

This seems like a potential solution: help.ubuntu.com/stable/ubuntu-help...

[Pacharapol Withayasakpunt]

Only that I cannot calibrate. My laptop is too old.

[Valts Liepiņš]

Have you tried importing ICM by itself?

The page I linked points out that using the settings is an alternative, to double clicking ICM file from file explorer.

You could also try more manual way, by following the Arch linux wiki guide: wiki.archlinux.org/index.php/ICC_p...
It should apply to your system as well, as under the hood both systems use xorg graphical stack.

[Pacharapol Withayasakpunt]

I have choices and I can see, as can be seen in the upmost screenshot.

However, I cannot truly tilt color settings to my preferences.

I also have installed DisplayCAL; but I cannot figure how it works at all.