Examine source code of Vinted Checker

{
  "manifest_version": 2,
  "name": "__MSG_ext_name__",
  "description": "__MSG_ext_description__",
  "version": "1.3",
  "default_locale": "fr",
  "permissions": [
    "activeTab",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "icons": {},
  "browser_specific_settings": {
    "gecko": {
      "id": "vinted-checker@yourdomain.com",
      "strict_min_version": "109.0"
    }
  }
}