Examine source code of Aintcy

{
  "manifest_version": 2,
  "name": "Calculator Add-on",
  "version": "1.0",
  "description": "A simple add-on that performs calculations",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{a103aff7-fb26-4222-aec7-d4216112230f}"
    }
  }
}