Facebook will soon offer its users a Messenger app that’s a little bit easier on the eyes.

The newest version of Messenger features a dark mode, which changes the app’s background from white to black and makes some other subtle display changes.

Dark backgrounds are believed to put less strain on human eyes than light ones. The Ontario Association of Optometrists recommends that people try to align screen brightness with the light level of the surrounding area.

Dark mode will be rolled out to all Messenger users in the near future, but anyone using it via the iOS or Android app can already activate it by sending a crescent moon emoji in any Messenger chat.