wl-gammactl VS gnome-gamma-tool

I don't know what you mean by color management - is it the calibration of the display with xrite/argyll?

For ICC profiles colormgr can help: https://wiki.archlinux.org/title/ICC_profiles#Wayland

If you just need basic brightness, contrast and gamma, wl-gammactl should do that: https://github.com/mischw/wl-gammactl

BTW Hyprland is not required, it's just the most practical way to have shortcuts key mappings in Wayland

However, this does not work in Wayland since it obviously belongs to the X Window System. I started searching the web for a possible solution and found wl-gammactl, which is a GUI for wlroots (https://github.com/mischw/wl-gammactl) and the gnome-gamma-tool (https://github.com/zb3/gnome-gamma-tool), but neither of them seemed to work because of missing dependencies, which can't be installed or invalid version numbers of required packages (e.g. found 1.20 but need: '>=1.23'). When attempting to build the gnome-gamma-tool, the following error message appears (despite Colord being installed):

It's very much possible with Wayland. Whether Plasma supports it is another question, unfortunately. Great program though, you can control it with commands and set an invert screen colors keybind.

What would be the best way to implement this? I tried wl-gammactl https://github.com/mischw/wl-gammactl with those settings but the screen just goes fully white?

Probably it just support sway as said here on github

Wayland is the protocol applications use to talk to compositors. What you need to control (this kind of-, since I assume you want a software overlay) brightness depends on the compositor/desktop environment you use. For wlroots based compositors (wayfire, sway) wl-gammactl or wlr-brightness could be useful. For Gnome (below version 40) the soft-brightness extension looks like what you need.

I purchased a mint condition T490 recently but I found the display to be inferior compared to the touchscreen of my T460. Both have 45% NTSC coverage but the T460 is pretty good in my opinion while I thought the T490 is too bright, almost washed out (it came with the standard FHD IPS AUO panel). Then I realized that it's actually the gamma that is too much for my liking and this is something that you can control from software. So I set it to 90% with this tool and voilá the display now has more contrast and looks much better to me. Difference is pretty big actually, it went from I want to replace it to it's perfectly fine in a blink of an eye. Absolutely recommended!

I haven't tried it yet myself, but gnome-gamma-tool looks promising.

Try using this

However, this does not work in Wayland since it obviously belongs to the X Window System. I started searching the web for a possible solution and found wl-gammactl, which is a GUI for wlroots (https://github.com/mischw/wl-gammactl) and the gnome-gamma-tool (https://github.com/zb3/gnome-gamma-tool), but neither of them seemed to work because of missing dependencies, which can't be installed or invalid version numbers of required packages (e.g. found 1.20 but need: '>=1.23'). When attempting to build the gnome-gamma-tool, the following error message appears (despite Colord being installed):