Examine source code of Dunkview

{
  "manifest_version": 2,
  "name": "Dunkview",
  "version": "1.1",
  "content_scripts": [
    {
      "matches": [
        "*://*.ign.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "19": "icon.png"
    },
    "default_popup": "popup.html"
  },
  "icons": {
    "128": "icon.png"
  }
}