Backups

Un/packing a package or file will overwrite already existing files if present. So if you unpack a file, make edits to the resulting file in the files/unpacked directory, and then unpack the file again, you overwrite all your changes from before. If your editor notices the difference and you refuse to reload the file and save again, you can restore it, but it's not good either way. That's why I highly recommend always keeping backups of your files, especially those in the packed binary form as with updates, the structure used in a .json, .txt or .c file might change.