chrome 点击上传文件选择框会延迟几秒才会显示 反应很慢

chrome52.0.2743.80以上，

accept: {
  title: 'Images',
  extensions: 'jpg,jpeg,png',
  mimeTypes: 'image/*'
}

改为

accept: {
  title: 'Images',
  extensions: 'jpg,jpeg,png',
  mimeTypes: 'image/jpg,image/jpeg,image/png'   //修改为这样
}