Please, a way to adjust Gamma?

Help
1

Where is the option, W ayland has no CLI option to adjust Gamma.

2

This may be outdated, but see and report back if anything of this works:

Wayland itself does not expose a universal “xrandr‑style” command line for gamma.
Instead you have to use whatever compositor you are running:

Compositor CLI / DBus way to change gamma
Sway / wlroots swaymsg output * gamma <R> <G> <B> (or per‑output)
KWin (Plasma) qdbus org.kde.KWin /KWin setGamma <R> <G> <B> (or via the “Display and Monitor → Gamma” KCM)
GNOME (Mutter) No native protocol; you can use the third‑party gnome‑gamma‑tool which creates a temporary ICC profile via D‑Bus
Other wlroots‑based compositors Look for a “gamma‑control” protocol (e.g. wl-gammactl) – many do not implement it yet.
3

tOk. I will try that. Can’t find in Pacman. I have Gammastep, how do I use it?

4

I am having package “tealdeer” which allows to run command:

$ tldr Gammastep

  Adjust the screen's color temperature according to the time of day.
  More information: <https://manned.org/gammastep>.

  Turn on Gammastep with a specific [t]emperature during the day (e.g. 5700k) and at night (e.g. 3600k):

      gammastep -t 5700:3600

  Turn on Gammastep with a manually specified custom [l]ocation:

      gammastep -l latitude:longitude

  Turn on Gammastep with a specific screen [b]rightness during the day (e.g. 70%) and at night (e.g. 40%), with minimum brightness 10% and maximum brightness 100%:

      gammastep -b 0.7:0.4

  Turn on Gammastep with custom [g]amma levels (between 0 and 1):

      gammastep -g red:green:blue

  Turn on Gammastep with a c[O]nstant unchanging color temperature:

      gammastep -O temperature

  Reset temperature adjustments applied by Gammastep:

      gammastep -x

and you should be able to also run “man Gammastep”. Post there if you have been able to find any command that does what you wanted.