Examine source code of Enable Google Analytics

{
  "manifest_version": 2,
  "name": "Google Analytics Debugger",
  "version": "1.0",
  "description": "Enable Google Analytics debugging on any site.",
  "icons": {
    "48": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "Enable GA Debugger"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{67664248-167d-427b-ac11-fa02f6973450}"
    }
  }
}