Examine source code of full-page-capture-pro

{
  "manifest_version": 2,
  "name": "Full Page Screenshot Pro",
  "version": "1.0.0",
  "description": "Capture high-detail, full-page screenshots in Firefox, including content below the fold, at full device pixel density.",
  "permissions": [
    "activeTab",
    "tabs",
    "<all_urls>",
    "downloads"
  ],
  "browser_action": {
    "default_title": "Capture full-page screenshot",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "fullpage-screenshot-pro@example.com",
      "strict_min_version": "78.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}