GLTF - Extra texture with skinned mesh

HTML

<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <title>My first three.js app</title>
    <script type="importmap">
      {
        "imports": {
          "three": "https://cdn.jsdelivr.net/npm/three@0.170.0/build/three.module.js",
          "three/addons/": "https://cdn.jsdelivr.net/npm/three@0.170.0/examples/jsm/"
        }
      }
    </script>
  </head>

  <body></body>
</html>

CSS

body {
  margin: 0;
}

.renderer-info {
  position: fixed;
  top: 10px;
  left: 10px;
  color: white;
  background-color: rgba(200, 200, 200, 0.5);
  font-family: monospace;
  font-size: 14px;
  padding: 10px;
}

button {
  color: white;
  background-color: rgba(200, 200, 200, 0.5);
  font-family: monospace;
  font-size: 12px;
  padding: 5px;
  cursor: pointer;
}

.dispose-button {
  position: fixed;
  top: 10px;
  right: 10px;
}

.animation-button-container {
  position: fixed;
  top: 60px;
  right: 10px;
  display: grid;
  gap: 4px;
}

.add-model {
  position: fixed;
  top: 80px;
  left: 10px;
}

JavaScript

import * as THREE from "three"
import { OrbitControls } from "three/addons/controls/OrbitControls.js"
import { GLTFLoader } from "three/addons/loaders/GLTFLoader.js"

let model
let animationActions = new Map()
let mixer

const scene = new THREE.Scene()
const camera = new THREE.PerspectiveCamera(
  75,
  window.innerWidth / window.innerHeight,
  0.1,
  1000,
)
const renderer = new THREE.WebGLRenderer()
const clock = new THREE.Clock()
const gltfLoader = new GLTFLoader()

window.renderer = renderer

renderer.setSize(window.innerWidth, window.innerHeight)
renderer.setPixelRatio(window.devicePixelRatio)
document.body.appendChild(renderer.domElement)

window.addEventListener('resize', () => {
  renderer.setSize(window.innerWidth, window.innerHeight);
  camera.aspect = window.innerWidth / window.innerHeight;
  camera.updateProjectionMatrix();
})

camera.position.z = 5
const controls = new OrbitControls(camera, renderer.domElement)
controls.enableDamping = true

let animationButtonContainer = document.createElement("div")
animationButtonContainer.className = "animation-button-container"
document.body.appendChild(animationButtonContainer)

/**
 * Add Model Input
 */

const addModel = document.createElement("input")
addModel.classList.add("add-model")
addModel.type = "file"
addModel.innerText = "Add Model"
document.body.appendChild(addModel)

const reader = new FileReader()

addModel.addEventListener("change", (e) => {
  const file = e.target.files[0]

  if (!file) {
    console.warn("No file")
    return
  }

  reader.onload = (e) => {
    const result = e.target.result

    if (!result) {
      console.warn("No result")
      return
    }

    gltfLoader.parse(result, "", (gltf) => {
      model = gltf.scene
      let animations = gltf.animations
      scene.add(model)

      if (animations && animations.length) {
        animationButtonContainer.innerHTML = ""

        mixer = new THREE.AnimationMixer(model)
        animations.forEach((clip) => {
          const action...