Examine source code of password-derivator

{
  "manifest_version": 2,
  "name": "password-derivator",
  "version": "0.1a",
  "description": "Stateless password derivator",
  "icons": {
    "48": "icons/lock.png"
  },
  "permissions": [],
  "browser_action": {
    "default_icon": {
      "48": "icons/lock.png"
    },
    "default_title": "password-derivator",
    "default_popup": "popup/password_derivator.html"
  }
}