Examine source code of NotSoLocalStorage

{
  "manifest_version": 2,
  "name": "NotSoLocalStorage",
  "version": "1.1",
  "license": "MIT",
  "description": "Sync localStorage across devices using Firefox Sync",
  "permissions": [
    "storage",
    "tabs",
    "<all_urls>",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/icon-32.png",
    "default_title": "LocalStorage Sync"
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "storagesync@yoavmoshe.com"
    },
    "gecko_android": {}
  }
}