Examine source code of Cookie Delete Minimal

{
  "manifest_version": 2,
  "name": "Cookie Delete Minimal",
  "version": "1.0",
  "permissions": [
    "tabs",
    "cookies",
    "storage",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Clear cookies",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{026a0f52-6eea-48f1-90d1-c7ea3e5031e6}"
    }
  }
}