and to test it here (it might be very loud!):

CTRL+SHIFT+I and in the console

    let o, a=new AudioContext();
    document.addEventListener("mousedown",function(){
      if (o) {o.stop(); o = undefined}
      else{ o=a.createOscillator(); o.type="sine"; o.frequency.value=100;
    o.connect(a.destination);o.start()}
    }) 

If you click anywhere it will start/stop.