2880x1800 is a 16:10 aspect ratio. If you use a wallpaper with a different ratio, ensure you select "Fill Screen" or "Stretch" to avoid black bars.
Finding the perfect for high-resolution screens (like the 15-inch MacBook Pro) depends on the specific shade you're looking for. A solid color background is often chosen to reduce eye strain and keep the desktop organized. Plain Green Options by Shade 2880x1800 Plain Green Wallpaper">
Here are direct links to 2880x1800 resolution solid color backgrounds: 2880x1800 is a 16:10 aspect ratio
One colour plain green solid color 2880x1800 wallpaper 4K HD [40+] Olive Green Desktop Wallpapers | WallpaperSafari Wallpaper Safari Tips for Using Solid Wallpapers 2880x1800 Plain Green Wallpaper">