In the desktop app, file saving is done in a safer manner so that if a problem occurs, any file that would have been overwritten should stay intact.
The desktop app now keeps short-term backups of your story library in case a bug occurs that affects the data on disk. It saves a backup copy of your library to a Backups folder in the main Twine folder when you first start it up, and every 20 minutes while Twine is running. It only keeps 10 backups at most, deleting older ones as needed, so this is not a full-fledged backup solution (and is not intended to be). It is intended as a way to restore data in the event of a crash or bug that overwrites data saved on disk.
The Chinese localization that should have appeared in 2.3.0 is in this version.