Examine source code of Offline Notes

{
  "manifest_version": 3,
  "name": "Offline Notes",
  "version": "1.2",
  "description": "A simple offline note-taking extension.",
  "icons": {
    "48": "icons/icon-48.png"
  },
  "action": {
    "default_icon": {
      "48": "icons/icon-48.png"
    },
    "default_popup": "popup.html",
    "default_title": "Offline Notes"
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "offlinenotes@philiplabs"
    }
  }
}