Facebook is working on a dark mode for Messenger, and it's a true AMOLED black theme. It's hidden away right now, but most of the code is there, ready and waiting to be enabled. By sending one command with root access, you can activate this feature right now.
Shout out to Redditor VincentJoshuaET who discovered the method we'll outline below. Sadly, this doesn't work for iPhones, and it won't work with standard ADB commands on Android — your phone has be rooted to try out the hidden dark mode in Messenger. But really, all you have to do is run a command in a terminal emulator app, tap a few options in a hidden menu, then enable dark mode in Messenger.
First, since the hidden/unactivated dark mode code is only included in the latest beta version of Facebook Messenger, you'll need to update the app. The easiest way to do that is to sideload the new version from APKMirror. Just tap the link below, then scroll down and hit "Download APK." From there, launch the file from your notification tray, then tap "Install" to update Messenger.
Once you've got the latest Facebook Messenger beta installed, make sure to open the app and log in. If you don't do this now, you won't be able to activate the hidden flags menu later.
You'll need to run a root command to activate dark mode, which means you'll need a terminal emulator app. You can use any such app of your choosing, but if you need a recommendation here, our pick is the tried and true Terminal Emulator by Jack Palevich.
- Play Store Link: Terminal Emulator (free)
Now, open your terminal emulator app and type in "su" (without the quotes), then hit enter on your keyboard. You'll be prompted to give the app Superuser access (Terminal Emulator, not Facebook Messenger), so tap "Grant" on the popup. You'll now notice the second command line starts with a hashtag instead of a dollar sign — this means the terminal is running with elevated privileges.
Next, copy the following command and paste it into the terminal prompt, then hit enter on your keyboard:
am start -n "com.facebook.orca/com.facebook.abtest.gkprefs.GkSettingsListActivity"
You'll immediately be taken to Facebook Messenger's hidden flags menu where low-level tweaks can be applied to the texting app. Tap "Search Gatekeepers" here, then type "dark" into the prompt and hit "OK."
Next, tap each of the results beneath the dark header to change their values from "NO" to "YES." When all three of these say "YES," back out of this menu, then fully close the Facebook Messenger app by swiping it away from your recent apps menu.
Now, reopen Messenger and tap your profile picture (or the silhouette icon) in the top-left corner to access the app's main settings menu. From here, scroll down to the Preferences section and you'll see a new option that wasn't there before — toggle "Dark Mode" on, then tap "OK" on the popup to verify your choice.
Messenger will now be fully black with white text and dark gray accents. Though the popup you just saw said dark mode "won't appear everywhere in Messenger," all of the main menus have received the dark mode treatment.