Examine source code of Button Popup Tool

{
  "manifest_version": 2,
  "name": "Button Popup Tool",
  "version": "1.1",
  "description": "Simple Firefox add-on with button and popup. No data collection.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_title": "Button Tool",
    "default_popup": "popup.html"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "button-popup-tool@example.com",
      "strict_min_version": "68.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}