Examine source code of SuperTunnel

{
  "manifest_version": 3,
  "name": "SuperTunnel",
  "version": "0.1.0",
  "description": "Browser proxy controller for SuperTunnel.",
  "action": {
    "default_popup": "extension/popup.html",
    "default_title": "SuperTunnel"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "permissions": [
    "proxy",
    "storage"
  ],
  "host_permissions": [
    "http://localhost:9002/*"
  ],
  "optional_host_permissions": [
    "http://*/*",
    "https://*/*"
  ],
  "icons": {
    "16": "extension/icons/16.png",
    "32": "extension/icons/32.png",
    "48": "extension/icons/48.png",
    "128": "extension/icons/128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "supertunnel@supertunnel.local",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}