Examine source code of Tabagotchi

{
  "manifest_version": 2,
  "name": "Tabagotchi",
  "short_name": "Tabagotchi",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "version": "1.0.1resigned1",
  "description": "A chrome extension that helps you be more productive. Fewer tabs = happy Tabagotchi. More tabs = angry Tabagotchi.",
  "homepage_url": "http://tabagotchi.com",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "background": {
    "scripts": [
      "src/js/background.js"
    ]
  },
  "permissions": [
    "storage",
    "tabs",
    "<all_urls>",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "tabagotchi.js"
      ],
      "run_at": "document_idle",
      "all_frames": false
    }
  ],
  "applications": {
    "gecko": {
      "id": "tabagotchi@addons.cool"
    }
  }
}