Amazon Prime Video Mouse Fix.js

// ==UserScript==
// @name         Amazon Prime Video Mouse Fix
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Fix mouse cursor while watching fullscreen video
// @author       Me
// @match        https://*.primevideo.com/*
// @match        http://*.primevideo.com/*
// @grant        none
// ==/UserScript==

(function() {
    "use strict";

    var mouseVisible = true;
    var timerHandle, playerElement;

    var mouseMove = () => {
        if (mouseVisible) {
            playerElement.style.cursor = "auto";
            clearTimeout( timerHandle );

            timerHandle = setTimeout( () => {
                playerElement.style.cursor = "none";
                mouseVisible = false;
                setTimeout( () => { mouseVisible = true; }, 200);
            }, 1500);
        }
    }

    document.addEventListener( "fullscreenchange", () => {
        try {
            var fullscreenElement = document.fullscreenElement ||
                                    document.webkitFullscreenElement ||
                                    document.mozFullScreenElement ||
                                    document.msFullscreenElement;

            if (fullscreenElement) {
                playerElement = fullscreenElement
                    .childNodes[1]
                    .childNodes[0]
                    .childNodes[0]
                    .childNodes[0]
                    .childNodes[1]
                    .childNodes[0]
                    .childNodes[2];
                document.addEventListener( "mousemove", mouseMove );
                mouseMove();
            } else {
                document.removeEventListener( "mousemove", mouseMove );
                clearTimeout( timerHandle );
                playerElement.style.cursor = "auto";
            }
        } catch(e) { return; }
    });
})();