The redesign of Facebook Messenger has been in the works for a very long time. The official rollout (for real this time) started just a few days ago, and users' opinions vary ever so much. I like the new interface personally, but that's just me. If you remember, Facebook also showed off a dark mode a couple of months ago. Unfortunately, the dark mode is not yet final, so it didn't make it to the redesign. The good news is we have found a way to enable it unofficially.
How to enable dark mode in Facebook Messenger now [Root]
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