With the Windows 10 Anniversary Update, Microsoft decided to add a dark design to Windows 10, as it has for years on Windows Phone. Last fall, Xbox users were given a light theme option, as the ability to choose between color schemes has become more popular.
Now the Dark Theme option is extended to File Explorer as first discovered by [Thurrott's Rafael] Rivera . The feature is hidden in Windows 10 build 17650 – which is only available to insiders on the "skip" option of the fast ring ̵
In the past, the system-wide theme setting has controlled various elements of the Windows 10 common user interface as well as various UWP apps. This could be the first time that the setting has touched a Win32 app like File Explorer. It's good news because dark topics were a fan favorite.
Of course, the feature is unannounced, so it is possible that it will eventually be scrapped or postponed until later. If all goes well, File Explorer will get its dark theme when Redstone 5 becomes available this fall.