Examine source code of Schultility

{
  "name": "Schultility",
  "description": "Schulnetz Utility Extension",
  "version": "2.0",
  "manifest_version": 3,
  "browser_specific_settings": {
    "gecko": {
      "id": "benjaminmikagerresheim@gmail.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage",
    "activeTab",
    "scripting"
  ],
  "action": {
    "default_popup": "/html/index.html",
    "default_icon": "/html/img/icon.png"
  }
}