Examine source code of Visual Tab Previews

{
  "manifest_version": 2,
  "name": "Visual Tab Previews",
  "version": "1.0",
  "description": "See large thumbnails of each open tab.",
  "permissions": [
    "tabs"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Visual Tab Previews"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a7a1c60b-e2af-48cb-8aa0-93f7a46d2e6a}"
    }
  }
}