Examine source code of Speed Test

{
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "128.png",
    "default_popup": "index.html"
  },
  "default_locale": "en",
  "description": "Speed Test",
  "icons": {
    "16": "16.png",
    "32": "32.png",
    "48": "48.png",
    "128": "128.png"
  },
  "manifest_version": 2,
  "name": "Speed Test",
  "short_name": "Speed Test",
  "version": "2.6.2"
}