The label read-only property of the TextTrack interface returns a human-readable label for the text track, if it is available.
A string containing the label, or an empty string.
In the following example the value of label is printed to the console.
let video = document.querySelector("video");
let track = video.addTextTrack("captions", "Captions", "en");
track.mode = "showing";
console.log(track.label);