Examine source code of Make Facebook Browsable

{
  "manifest_version": 2,
  "name": "Make Facebook Browsable",
  "description": "Makes Facebook slightly more usable when you're not logged in.",
  "version": "1.0",
  "icons": {
    "128": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png"
  },
  "permissions": [
    "https://*.facebook.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*.facebook.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "facebook.css"
  ]
}