Examine source code of Health Tips Widget

{
  "manifest_version": 2,
  "name": "Health Tips Widget",
  "version": "1.0",
  "description": "A simple widget that shows daily health tips.",
  "permissions": [],
  "browser_action": {
    "default_popup": "index.html",
    "default_icon": {
      "128": "images/heath-logo.png"
    }
  },
  "icons": {
    "128": "images/heath-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b9c1e042-327a-43ca-a2c7-e41cd05b9b69}"
    }
  }
}