Examine source code of Bulk File Downloader

{
  "manifest_version": 3,
  "name": "Bulk File Downloader",
  "version": "1.0.0",
  "description": "Download any file from any page. Free: one at a time. Pro: all at once + ZIP.",
  "browser_specific_settings": {
    "gecko": {
      "id": "bulk-file-downloader@extension",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "downloads",
    "storage",
    "scripting",
    "activeTab"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "service-worker.js"
    ],
    "type": "module"
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "lib/jszip.min.js",
        "lib/jszip-esm.js"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'; connect-src https://api.gumroad.com *"
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}