id property contains a
string which uniquely identifies the track represented by the
VideoTrack. This ID can be used with the
VideoTrackList.getTrackById() method to locate a specific track within
the media associated with a media element.
The track ID can also be used as the fragment of a URL that loads the specific track (if the media supports media fragments).
var trackID = VideoTrack.id;
|HTML Living Standard
The definition of 'VideoTrack: id' in that specification.
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