Examine source code of MemoryTabs

{
  "manifest_version": 2,
  "name": "MemoryTabs",
  "version": "1.0",
  "description": "Memorize the order of open tab thumbnails.",
  "permissions": [
    "tabs"
  ],
  "browser_action": {
    "default_title": "MemoryTabs",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "memorytabs@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}