Examine source code of WNG Site Selector

{
  "manifest_version": 2,
  "name": "WNG Site Selector",
  "description": "Easily switch between ETC and PTC.",
  "version": "1.1resigned1",
  "icons": {
    "128": "alamo.png"
  },
  "page_action": {
    "default_icon": {
      "16": "alamo.png",
      "24": "alamo.png",
      "32": "alamo.png"
    },
    "default_title": "WNG Site Selector",
    "default_popup": ""
  },
  "permissions": [
    "declarativeContent",
    "cookies",
    "webNavigation",
    "webRequest",
    "webRequestBlocking",
    "*://*.alamo.com/",
    "*://*.nationalcar.com/",
    "*://*.alamo.ca/",
    "*://*.nationalcar.ca/"
  ],
  "web_accessible_resources": [
    "etc.png",
    "ptc.png"
  ],
  "background": {
    "scripts": [
      "eventPage.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{95f6787e-f19d-4465-9505-59c37f0536a3}"
    }
  }
}