Examine source code of Browser Lock

{
  "manifest_version": 2,
  "name": "Simple Browser Lock",
  "version": "3.0",
  "description": "Locks the browser on startup requiring a password.",
  "browser_specific_settings": {
    "gecko": {
      "id": "{55334281-1803-444b-914b-731e1809fc7a}"
    }
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/lock-48.png",
    "default_title": "Browser Lock Settings"
  },
  "icons": {
    "48": "icons/lock-48.png"
  }
}