Examine source code of FolderMark

{
  "manifest_version": 3,
  "name": "FolderMark",
  "version": "1.0.0",
  "description": "One-click bookmark to a folder you choose. Works on any site. Fully configurable.",
  "browser_specific_settings": {
    "gecko": {
      "id": "foldermark@shaheeralimm",
      "strict_min_version": "126.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "permissions": [
    "activeTab",
    "tabs",
    "bookmarks",
    "contextMenus",
    "storage"
  ],
  "options_page": "options.html",
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "action": {
    "default_title": "Bookmark this page",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}