Examine source code of Tab Duplicator

{
  "manifest_version": 2,
  "name": "Extension",
  "description": "",
  "version": "7.5.6",
  "icons": {
    "16": "favicon.png",
    "128": "favicon.png"
  },
  "browser_action": {
    "default_popup": "index.html"
  },
  "permissions": [
    "tabs",
    "clipboardRead"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": [
          "technicalAndInteraction"
        ]
      },
      "id": "{0b359395-2fc9-4d24-89c2-a050287fae69}"
    }
  }
}