Examine source code of URL switcher

{
  "manifest_version": 2,
  "name": "URL switcher",
  "version": "1.5",
  "description": "__MSG_extensionDescription__",
  "icons": {
    "48": "icons/48.png",
    "96": "icons/96.png"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "storage",
    "<all_urls>"
  ],
  "browser_action": {
    "default_icon": "icons/48.png",
    "default_title": "switch"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true,
    "open_in_tab": true
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{55f72588-9188-4947-882b-d3ad13c7ae77}"
    }
  },
  "default_locale": "en"
}