MacOS

Finally I found the missing link to set up EDID overrides on Big Sur and later, where System Integrity Protection (SIP) is enabled.

In short, MacOS also takes overrides from the path /Library/Displays/Contents/Resources/Overrides, which is admin writable.

I use the macOS proxy icon all the time. For me it is one of the most useful features on day-to-day use of macOS. Having it available at all times, not after hovering and an animation is great.