The position property of the VTTCue interface represents the indentation of the cue within the line.

A number, or "auto" representing the indentation of the cue within the line.

In the following example a new VTTCue is created, then the value of position is set to 2. The value is then printed to the console.

let video = document.querySelector("video");
let track = video.addTextTrack("captions", "Captions", "en");
track.mode = "showing";

let cue1 = new VTTCue(0, 0.9, "Hildy!");
cue1.position = "2";
console.log(cue1.position);

track.addCue(cue1);