Examine source code of github hide banner

{
  "manifest_version": 2,
  "name": "github hide banner",
  "version": "1.1resigned1",
  "description": "Hides GitHub Signup banner for each repository.",
  "content_scripts": [
    {
      "matches": [
        "*://github.com/*"
      ],
      "js": [
        "app.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{46d20226-d03c-4263-a458-fd9a98ef397a}"
    }
  }
}