I have a JS program that plays an audio until the very end.
I noticed than audio.duration slightly changes at the end of the audio, seemingly to have 0 <= audio.currentTime <= audio.duration always hold true :

let audio = new Audio(...)
audio.play()
function printAudioDuration() {
  window.requestAnimationFrame(() => {
    console.log(audio.duration)
    printAudioDuration()
  )
}

That results in :

132.623667
132.623667
132.623667
...
132.623667
132.623673

And if I print audio.currentTime along the way, I always get a timestamp smaller than 132.623667, except for the last one, which exactly equals 132.623673.

Is this a documented behavior ? Am I doing something wrong ?