Examine source code of Comic Sans for Twitter

{
  "manifest_version": 2,
  "name": "Comic Sans for Twitter",
  "version": "1.0",
  "homepage_url": "https://defer.cc",
  "description": "Twitter with Comic Sans",
  "icons": {
    "48": "icons/cs4twitter-48.png"
  },
  "web_accessible_resources": [
    "sheet.css"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.twitter.com/*"
      ],
      "js": [
        "cs4twitter.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d0e7e5c8-b096-4847-ba5a-e4fd9839b8c4}"
    }
  }
}