OptionalcontentOptionalextractOptionalforOptionalforOptionalheightOptionalisOptionalisOptionalisOptionalisOptionalisOptionalmediaOptionalmusicOptionaloffsetOptionaluploadOptionaluploadOptional InternalvideoThe edits the library itself declares for the file's tracks (video_edit_params): the Reel with a
song is a file the library wrote, so the layout it wrote names the supplemental sound track. Not a
developer input.
OptionalwaterfallOptionalwidthOptionalx
The earlier way a song reached a Reel: the server burns it into the video. The platform that does not model the music player (iOS) keeps it; the Android Reel bakes the song into the file instead.