The addCue() method of the TextTrack interface adds a new cue to the list of cues.

cue

A TextTrackCue.

Undefined.

InvalidStateError DOMException

Thrown if the rules for this TextTrackList do not match those that are appropriate for the incoming TextTrackCue.

In the following example two cues are added to a video text track using addCue().

let video = document.querySelector("video");
let track = video.addTextTrack("captions", "Captions", "en");
track.mode = "showing";
track.addCue(new VTTCue(0, 0.9, "Hildy!"));
track.addCue(new VTTCue(1, 1.4, "How are you?"));