Examine source code of Bookmark URL Updater

{
  "manifest_version": 2,
  "name": "Bookmark URL Updater",
  "version": "0.2.1",
  "description": "Update bookmark URL when visited",
  "author": "Max Caulfield",
  "permissions": [
    "bookmarks",
    "tabs",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "icons": {
    "48": "icons/bookmark-48.png",
    "96": "icons/bookmark-96.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/bookmark-48.png",
      "96": "icons/bookmark-96.png"
    },
    "default_title": "Bookmark URL Updater"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{56ec7e76-d3bd-4024-8ff6-b80c132032e6}"
    }
  }
}