Examine source code of Sign PDF Cloud

{
  "manifest_version": 3,
  "name": "Sign PDF Cloud",
  "version": "1.0.0",
  "description": "Send PDFs for e-signature, manage templates, and track envelopes from your browser.",
  "browser_specific_settings": {
    "gecko": {
      "id": "sign-pdf-cloud@signpdf.cloud",
      "strict_min_version": "115.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "websiteContent"
        ]
      }
    }
  },
  "permissions": [
    "contextMenus",
    "notifications",
    "storage",
    "alarms",
    "downloads",
    "activeTab"
  ],
  "host_permissions": [
    "https://signpdf.cloud/*",
    "https://*.signpdf.cloud/*",
    "http://localhost/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "action": {
    "default_popup": "popup.html",
    "default_title": "Sign PDF Cloud",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  }
}