Examine source code of Return Old GitHub Feed

{
  "name": "Return Old GitHub Feed",
  "description": "Returns the actually usable feed design",
  "version": "1.0.1",
  "manifest_version": 2,
  "permissions": [
    "activeTab"
  ],
  "icons": {
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://github.com/*"
      ],
      "js": [
        "replace.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9dfcb52a-5322-4d42-9924-9d3b8871ad90}"
    }
  }
}