Examine source code of Savings Calculator

{
  "manifest_version": 2,
  "name": "Savings Calculator",
  "description": "Project the growth and future value of your money over time.",
  "version": "1.0.1",
  "browser_action": {
    "default_popup": "index.html",
    "default_title": "Savings Calculator"
  },
  "icons": {
    "16": "img/icon16.png",
    "32": "img/icon32.png",
    "64": "img/icon64.png",
    "128": "img/icon128.png"
  }
}