Examine source code of Custom Title

{
  "manifest_version": 2,
  "name": "Custom Title",
  "version": "2.0",
  "description": "Add a tag to identify the current profile to the window title",
  "homepage_url": "https://github.com/toonn/CustomTitle",
  "icons": {
    "48": "icons/CustomTitle-48.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "CustomTitle.js"
      ]
    }
  ],
  "permissions": [
    "storage"
  ]
}