Examine source code of Japan Dashboard

{
  "manifest_version": 2,
  "name": "Japan Dashboard",
  "version": "1.3",
  "description": "Zeigt japanische Uhrzeit, Währungskurs und Wetterdaten an.",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "browser_specific_settings": {
    "gecko": {
      "id": "{43d1234b-9f94-444a-a623-412ef2c8c3fd}"
    }
  }
}