Examine source code of Persian Twitter

{
  "name": "__MSG_appName__",
  "version": "2.3.1resigned1",
  "manifest_version": 2,
  "description": "__MSG_appDescription__",
  "icons": {
    "16": "images/persian-twitter-16.png",
    "128": "images/persian-twitter-128.png"
  },
  "default_locale": "en",
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "permissions": [
    "tabs"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://twitter.com/*",
        "https://tweetdeck.twitter.com/"
      ],
      "js": [
        "scripts/contentscript.js"
      ],
      "css": [
        "styles/page-firefox.css"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "page_action": {
    "default_icon": {
      "19": "images/persian-twitter-19.png",
      "38": "images/persian-twitter-38.png"
    },
    "default_title": "Persian Twitter",
    "default_popup": "popup.html"
  },
  "web_accessible_resources": [
    "fonts/*.woff",
    "fonts/*.woff2"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5b81b126-9c7f-4ae3-9c53-b0a61dd3f3c9}"
    }
  }
}