Examine source code of Measure Converter

{
  "manifest_version": 2,
  "browser_action": {
    "default_icon": "img/logo-32.png",
    "default_popup": "index.html",
    "default_title": "Measure Converter"
  },
  "name": "Measure Converter",
  "author": "Lionel Mahistre",
  "description": "This addon instantly converts measurements from and to different units.",
  "version": "1.2.1",
  "icons": {
    "32": "img/logo-32.png",
    "48": "img/logo-48.png",
    "64": "img/logo-64.png",
    "96": "img/logo-96.png",
    "128": "img/logo-128.png",
    "512": "img/logo-512.png"
  }
}