The id of the media track that is used to identify and set the track.
Optional
isIndicates whether the subtitle is fragmented.
Optional
isIndicates whether the subtitle is sideloaded, i.e. it has been added through PlayerSubtitlesAPI.add or SourceConfig.subtitleTracks.
8.177.0
The subtitle type, either "caption" or "subtitle" (default: "subtitle").
The text used to represent this track to the user (e.g. in the UI).
The language of the subtitle/caption track.
Optional
roleThe optional roles of the track.
Optional
urlThe URL to the associated file.
Definition of a text track.