Examine source code of NoYoutubeAvatars

{
  "manifest_version": 2,
  "name": "NoAvatars",
  "version": "1.1",
  "description": "Remove Chat Avatars",
  "icons": {
    "32": "icons/close.png"
  },
  "browser_action": {
    "default_title": "NoAvatars",
    "default_icon": "icons/close.png",
    "default_popup": "menu.html"
  },
  "applications": {
    "gecko": {
      "id": "notarealexpram@gmail.com",
      "strict_min_version": "45.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/watch?v=*"
      ],
      "js": [
        "js/jquery.js",
        "noava.js"
      ]
    }
  ],
  "permissions": [
    "activeTab",
    "storage"
  ]
}