Examine source code of Event Tracking Tracker

{
  "name": "Event Tracking Tracker",
  "version": "1.1.6",
  "manifest_version": 2,
  "description": "Plugin to track Google Analytics Event Tracker event calls",
  "browser_action": {
    "default_icon": "ett.png"
  },
  "icons": {
    "16": "ett16.png",
    "48": "ett48.png",
    "128": "ett.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "permissions": [
    "storage",
    "webRequest",
    "tabs",
    "http://*/*",
    "https://*/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{de98ee30-617e-4d1a-b2a4-715b5bdb9863}"
    }
  }
}