Examine source code of B64Tool

{
  "description": "Popup a box to do base64 encoding and decoding",
  "manifest_version": 2,
  "name": "B64Tool",
  "version": "0.0.1",
  "homepage_url": "http://test.com",
  "icons": {
    "32": "icons/32.png",
    "48": "icons/48.png"
  },
  "browser_action": {
    "default_icon": "icons/32.png",
    "default_title": "B64Tool",
    "default_popup": "popup/b64.html"
  }
}