JSFiddle - React, Tailwind, and code Playground

HTML

<html>
<head>
    <title>ThreeJs lots of cubes</title>
    <meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
    <style>
        body {
            font-family: Monospace;
            background-color: #000;
            color: #fff;
            margin: 0px;
            overflow: hidden;
        }

    </style>
</head>
<body>
<script src="https://threejs.org/build/three.js"></script>
<script src="https://threejs.org/examples/js/libs/stats.min.js"></script>
<script src="https://threejs.org/examples/js/controls/TrackballControls.js"></script>

<script>
    var container, stats;

    var camera, controls, scene, renderer;

    var gridSize = 20;

    init();
    animate();

    function init() {

        camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 0.01, 1e10);

        scene = new THREE.Scene();
        //DON'T AUTO UPDATE MATRIX IN EACH FRAME
        scene.autoUpdate = false;
        scene.add(camera);

        controls = new THREE.TrackballControls(camera);

        controls.rotateSpeed = 5.0;
        controls.zoomSpeed = 5;
        controls.panSpeed = 2;

        controls.noZoom = false;
        controls.noPan = false;

        controls.staticMoving = true;
        controls.dynamicDampingFactor = 0.3;

        var light1 = new THREE.DirectionalLight(0xFFFFFF, 0.8);
        light1.position.set(1, 2, 3);
        scene.add(light1);

        var light2 = new THREE.HemisphereLight( 0xffffbb, 0x080820, 0.8 );
        scene.add( light2 );
        
        light1.updateMatrixWorld(true);
        light2.updateMatrixWorld(true);

        var geometry = new THREE.BoxBufferGeometry(0.8, 0.8, 0.8);
        var material = new THREE.MeshPhongMaterial({color: 0xeeeeee});

        for (var x = 0; x < gridSize; x++)
            for (var y = 0; y < gridSize; y++)
                for (var z = 0; z < gridSize; z++) {
                    var boxMesh = new THREE.Mesh(geometry, material);
     ...