Examine source code of Link Note Saver

{
  "manifest_version": 3,
  "version": "1.1",
  "name": "Link Note Saver",
  "action": {
    "default_popup": "index.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "linknotesaver@usernameb99.com"
    }
  }
}