Media player playlist (such as .m3u8) are basically text files that contain list of multimedia files to be played in specific order. As such you do not need to convert m3u8 to txt files, you can open playlists using any text editor and edit them should you need it, regardless of their actual file extension.
This type of m3u8 to txt conversion is mainly useful when users want to check the location of the multimedia files listed in the playlist.