Found this picture in 4K resolution https://hdwallpapers.pro/imac-stripes-on-desktop

I can suggest 4K or bigger resolution wallpaper site https://hdwallpapers.pro/ there is function: “Download your resolution” so I can download in few seconds my favorite wallpaper for any device at home 3840x1080 Dual Monitor system, at work Full HD notebook and also on my iPad Air.