Sequoia 15.4 : Setting a custom desktop color does not work

I'm looking for an Easter Egg hidden in the screensaver trees - but yes: Apple seem to spend a lot of effort on the fancy stuff like "a perfect walk though sunlit woodland" but not the simple stuff like "what color would you like to stare at for the next 8 hours?"

I had same bug. Got it working by clicking the + icon in the color swatches area to add a custom color, then pick a color from the picker. It won't update the background yet. Next you have to click the "show all" above the colored circles to see the color you just added to the swatches. Pick the color from the swatches now and it will apply.

Apple … is it that hard to test before delivery?

Apple will not see your complaint here. We are all other end users, We cannot fix.

If you truly desire to place this where an Apple employee will see it, this is the only way:

Feedback - macOS - Apple

Known issue. There are several ways to do so, but the solution is to create a tiny image in the color you want to use, then put that image in the Pictures folder of your user account so you can choose it in Settings.

Custom wallpaper color shows as white and… - Apple Community

Known bug. Have to wait until next update.

I cannot set a custom color - Only the colors that are available in the settings "Wallpaper".

Didn't work for me. Still just 19 colors.

I've discovered this bug too. As a workaround I took a screen grab of the blue coloured desktop on an earlier MB Pro running Monterey. I copied the screen grab pic to the desktop on my MB Pro running Sequoia 15.4 which I then added to the available photos in the wallpaper setting option.

Read the post above yours.