Facebook seems to be testing a new night mode setting for its messenger app. This would make the standard blue and white to be replaced essentially by black and white though what would be particularly soothing for the eye is that the acres of white would take on a black hue, thereby making it much more soothing for the eye.
The change in the UI is however applicable to users in select countries only; and that too for only a handful of users in those regions. Also, this being just a test, there is no guarantee the same would prevail or will be rolled out to all users subsequently. Or worse, the dark theme might never get to be implemented at all if the tests fail to evoke the desired results.
The dark theme meanwhile is available in the ‘Me’ section of the Messenger app though there also is a warning message shown stating that the UI change is a work in progress thing. This also means there might be shortcomings in the new setting where the dark theme might seem inconsistent across some sections. In fact, users might find the effect even blinding in some situations as well.
As for the implementation itself, the white background has all been taken over by black while the texts are in white. All of this makes it extremely easy for the eye to decipher things while still being easy on the eye. Some texts like those in the search bar are shown in grey though in a darker theme to make it stand out from the black background.
Also, another inherent advantage with the dark theme is that it is a lot more battery efficient as well. Notably, YouTube too has adopted a dark theme in the recent past. That makes it a high probability for Facebook to follow suit though the company is yet to commit anything of that just yet.