Examine source code of Botcheck.me

{
  "manifest_version": 2,
  "name": "Botcheck.me",
  "short_name": "Botcheck.me",
  "version": "3.3resigned1",
  "description": "Uses machine learning techniques to detect accounts with automated political behavior on Twitter.",
  "icons": {
    "128": "icons/default@128-gray-square.png"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "content_scripts": [
    {
      "css": [
        "injected.css"
      ],
      "js": [
        "injected.js"
      ],
      "matches": [
        "https://twitter.com/*"
      ]
    }
  ],
  "background": {
    "scripts": [
      "vendor/browser-polyfill.js",
      "content/namespace.js",
      "content/util.js",
      "background/index.js",
      "background/storage.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/default@16-gray.png",
      "128": "icons/default@128-gray.png"
    }
  },
  "permissions": [
    "storage",
    "tabs",
    "https://botcheck2-dot-surfsafe-rbl.appspot.com/*"
  ],
  "web_accessible_resources": [
    "*.ttf",
    "*.woff",
    "*.png",
    "*.svg"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5451c9ca-567d-4e26-9241-a9ff988f5059}"
    }
  }
}