Examine source code of Bookmark to RSS-Librarian

{
  "manifest_version": 3,
  "name": "Bookmark to RSS-Librarian",
  "version": "1.0",
  "description": "Sends the page to your specified RSS-Librarian user when you hit the bookmark button.",
  "browser_specific_settings": {
    "gecko": {
      "id": "9k8hgy8jp@mozmail.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "background": {
    "scripts": [
      "script.js"
    ]
  },
  "permissions": [
    "storage",
    "bookmarks",
    "webRequest"
  ]
}