Examine source code of Twitter-Free Mornings

{
  "manifest_version": 2,
  "name": "Twitter-Free Mornings",
  "description": "Silence the noise for a bit every morning.",
  "version": "0.3",
  "content_scripts": [
    {
      "matches": [
        "https://twitter.com/*",
        "http://twitter.com/*"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "icons": {
    "16": "images/twitter-mornings-16.png",
    "32": "images/twitter-mornings-32.png",
    "48": "images/twitter-mornings-48.png",
    "128": "images/twitter-mornings-128.png"
  },
  "web_accessible_resources": [
    "script.js"
  ],
  "permissions": [
    "http://twitter.com/",
    "https://twitter.com/"
  ]
}