Examine source code of Keep or Delete Bookmarks

{
  "manifest_version": 3,
  "name": "__MSG_extension_name__",
  "version": "3.0.0",
  "description": "__MSG_extension_description__",
  "icons": {
    "48": "images/icon.svg"
  },
  "developer": {
    "name": "Sören Hentzschel",
    "url": "https://www.soeren-hentzschel.at/firefox-webextensions/keep-or-delete-bookmarks/?utm_campaign=webext&utm_term=keep-or-delete-bookmarks"
  },
  "background": {
    "scripts": [
      "js/core/background.js"
    ]
  },
  "action": {
    "browser_style": false,
    "default_icon": "images/icon.svg",
    "default_title": "__MSG_extension_name__"
  },
  "permissions": [
    "bookmarks",
    "menus",
    "storage",
    "tabs"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self';"
  },
  "options_ui": {
    "page": "html/options.html",
    "open_in_tab": true
  },
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "keep-or-delete-bookmarks@agenedia.com",
      "strict_min_version": "109.0"
    }
  }
}