nvidia-settings if you're using the proprietary driver.
Yup. Found it under the Monitor option, works great.
There are color settings in pretty much every desktop environment. I’m not sure where to find them on others, but in Gnome they’re in the Settings app under “Colors”.
What do I do for Window managers ? I Haven't tried a DE other than xfce in years. Maybe it's my cue to try Plasma or Gnome.
It looks like for Xfce, it’s called “Color Profiles” in the settings. From the screenshots it looks like it works the same as Gnome’s.
You've likely searched for this and found https://github.com/libvibrant/vibrantLinux
I don't have an NVIDIA card but this might be what you want, maybe?
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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