This option allows for the safe use of distinct filesystem snapshots of games with some cores (e.g., DosBox). Keep in mind that with this option enabled, game changes won't be saved (the unique save folder will be deleted on exit) until you explicitly call the save (or share) function. Thus, you will need files like dosbox.conf along with the games to use some default behaviors with each new game session.
The main benefit of libyuv, apart from shortening the video pipeline, is quite noticeable latency and CPU usage decrease due to various assembler/SIMD optimizations of the library. However, there is a drawback for macOS systems: libyuv cannot be downloaded as a compiled library and can only be built from the source, which means we should include a cropped source code of the library (~10K LoC) into the app or rise the complexity of macOS dev and run toolchains. The main target system -- Linux, and Windows will use compiled lib from the package managers and macOS will use the lib included as a shortened source-code.
Building the app with the no_libyuv tag will force it to use libyuv from the provided source files.