Examine source code of News Feed for GitHub

{
  "manifest_version": 2,
  "name": "News Feed for GitHub",
  "description": "GitHub news feed notifications directly in the browser",
  "version": "1.2.2resigned1",
  "homepage_url": "https://github.com/julmot/news-feed-for-github",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "applications": {
    "gecko": {
      "id": "{90973394-D193-11E5-A96D-6AD3BB8E7F8B}",
      "strict_min_version": "45.0"
    }
  },
  "minimum_chrome_version": "42",
  "browser_action": {
    "default_icon": {
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    },
    "default_title": "News Feed for GitHub",
    "browser_style": false
  },
  "permissions": [
    "https://*.github.com/*",
    "https://*.githubusercontent.com/*",
    "notifications",
    "tabs"
  ],
  "background": {
    "scripts": [
      "vendor/xmlToJSON.js/lib/xmlToJSON.js",
      "scripts/NewsFeed.js",
      "scripts/NewsFeedChecker.js",
      "scripts/NewsFeedTransmitter.js",
      "scripts/bootstrap.js"
    ]
  }
}