Examine source code of Cryptool

{
  "manifest_version": 3,
  "name": "Cryptool",
  "version": "1.3.0",
  "description": "A secure, local-only viewer for AES-256 and PGP symmetric encrypted memos. Decrypts files in your browser without uploading data, supporting both modern AES-GCM and standard PGP formats.",
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon.png"
  },
  "action": {
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon.png"
    }
  },
  "options_ui": {
    "page": "viewer.html",
    "open_in_tab": true
  },
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "cryptool@ifritjp.github.io",
      "strict_min_version": "120.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'none'"
  },
  "permissions": [],
  "host_permissions": []
}