Easily Control Mac Dark Mode with NightOwl.How macOS Dark Mode Works with Some Apps and Features.So here’s out how to turn on Dark Mode. It’s especially useful when working at night and helps you focus. It will change the menu bar’s appearance and the stock apps to make things easier on the eyes. It is available on macOS Mojave and later and can be turned on to work across the entire system. From reducing eye strain to improving battery life, Dark Mode has varying benefits.