Examine source code of Note Pro

{
  "manifest_version": 3,
  "name": "Note Pro",
  "version": "3.0.0",
  "description": "A notepad in your browser's side panel. Your notes stay on your own device: no account, no server, no sync.",
  "permissions": [
    "tabs"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'none'; img-src 'self' data: blob:"
  },
  "action": {
    "default_title": "Open Note Pro",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "sidebar_action": {
    "default_title": "Note Pro",
    "default_panel": "sidebar.html",
    "default_icon": "icons/icon-48.png",
    "open_at_install": false
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "sidenote@nation.tools",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "strict_min_version": "142.0"
    }
  }
}