Examine source code of No FB at Work Plugin

{
  "manifest_version": 2,
  "name": "No FB at Work Plugin",
  "description": "This extension will remove like, share, and comment",
  "version": "1.0",
  "browser_action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.facebook.com/*"
      ],
      "js": [
        "index.js"
      ]
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "applications": {
    "gecko": {
      "id": "no_fb@adin234.com"
    }
  }
}