콘텐츠 로딩을 최적화하기 위해 JavaScript에서 유휴 시간을 어떻게 감지할 수 있습니까?

var inactivityTime = function () {
    var time;
    // Reset inactivity timer on page load and DOM events
    window.onload = resetTimer;
    document.onmousemove = resetTimer;
    document.onkeydown = resetTimer;

    function logout() {
        // Log out or perform any desired action upon idle time
        alert("You are now logged out.")
    }

    function resetTimer() {
        // Clear the timeout and set a new one for the idle time period
        clearTimeout(time);
        time = setTimeout(logout, 3000);
    }
};

window.onload = function() {
  inactivityTime();
}

document.onload
document.onmousemove
document.onmousedown
document.ontouchstart
document.onclick
document.onkeydown

window.addEventListener('load', resetTimer, true);
var events = ['mousedown', 'mousemove', 'keypress', 'scroll', 'touchstart'];
events.forEach(function(name) {
 document.addEventListener(name, resetTimer, true);
});