Examine source code of Unauth Group List

{
  "manifest_version": 2,
  "name": "Unauth Group List",
  "version": "1.0",
  "description": "Adds a list of groups to the header.",
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.vk.com/*"
      ],
      "js": [
        "group.js"
      ],
      "css": [
        "dropdown.css"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{daf64bf7-a46e-4460-976c-91cf07634c3d}"
    }
  }
}