Examine source code of Noio

{
  "manifest_version": 2,
  "name": "Noio",
  "version": "1.1resigned1",
  "description": "Replaces any .io websites you go to with a nice picture",
  "icons": {
    "48": "icons/noio-48.png",
    "96": "icons/noio-96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.io/*"
      ],
      "js": [
        "noio.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{15c3b901-5a39-4ed4-9c6c-fdfdc1a39477}"
    }
  }
}