Examine source code of Rollcall

{
  "manifest_version": 2,
  "name": "Rollcall",
  "version": "1.2.1",
  "description": "A simple tool that checks to see which of your Planetside 2 friends are online",
  "homepage_url": "https://github.com/adrien-timmer/rollcall",
  "icons": {
    "48": "icons/rollcall-48.png",
    "96": "icons/rollcall-96.png",
    "128": "icons/rollcall-128.png"
  },
  "permissions": [
    "webRequest",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/rollcall-32.png",
    "default_title": "Rollcall",
    "default_popup": "popup/home/home.html"
  }
}