Examine source code of Performance-Analyser

{
  "manifest_version": 2,
  "name": "performance-analyser",
  "version": "1.7.1",
  "description": "Get insight into the performance of the website in the current tab - sort of a mini live version of WebPageTest",
  "homepage_url": "https://github.com/micmro/performance-bookmarklet",
  "icons": {
    "16": "data/images/icon16.png",
    "19": "data/images/icon19.png",
    "32": "data/images/icon32.png",
    "38": "data/images/icon38.png",
    "48": "data/images/icon48.png",
    "58": "data/images/icon58.png",
    "64": "data/images/icon64.png",
    "128": "data/images/icon128.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_title": "Performance Analyser"
  },
  "background": {
    "scripts": [
      "data/trigger.js"
    ]
  }
}