Examine source code of Twitter Bad

{
  "manifest_version": 2,
  "name": "Twitter Bad",
  "version": "0.1",
  "description": "Twitter is bad. This extension replaces twitter with a message telling you that twitter is bad, thus preventing you from using twitter, because it is bad.",
  "icons": {
    "48": "icons/48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitter.com/*"
      ],
      "js": [
        "bad.js"
      ]
    }
  ]
}