The color scheme can be more manageable on the eyes when scrolling through your newsfeed or a set of videos, especially at night.
We've reached out to Facebook for comment to find out why it's been switched off for certain users.
How to check if you have dark mode
Dark mode can be difficult to find on iOS or Android, as it's not as visible as other features. On the main screen, go to the 'Menu' icon on the navigation bar, then Settings & Privacy, scroll down to Preferences, and Dark Mode should be there.
However, for the desktop it's an easier affair by simply going to the arrow on the top right, selecting 'Display and Accessibility', and switching on dark mode.
There hasn't been an explanation from Meta as to why it's decided to switch off the feature for some, nor is there a reason regardless to do it. It's a useful feature, and it won't be a strain on the company or the apps it offers, so the deactivation is a baffling decision.
For the time being, we recommend removing the app from your Android or iOS device, reinstalling it, and see whether that makes dark mode return as an option.
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Daryl had been freelancing for 3 years before joining TechRadar, now reporting on everything software-related. In his spare time he's written a book, 'The Making of Tomb Raider', alongside podcasting and usually found playing games old and new on his PC and MacBook Pro. If you have a story about an updated app, one that's about to launch, or just anything Software-related, drop him a line.