Examine source code of metafilter-navigator

{
  "manifest_version": 2,
  "name": "metafilter-navigator",
  "version": "1.4resigned1",
  "description": "Unofficial Metafilter web extension of provide better navigation.",
  "icons": {
    "48": "icons/icon-48.png",
    "64": "icons/icon-64.png",
    "128": "icons/icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.metafilter.com/*"
      ],
      "js": [
        "content/index.js"
      ],
      "css": [
        "content/index.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{80a14d79-df62-4b3b-968a-39f04848a258}"
    }
  }
}