I notice you're asking about "FatXplorer extend code" — but this phrasing is ambiguous and could relate to a few different things.
// C# example: Watch for FATX mount point FileSystemWatcher watcher = new FileSystemWatcher("X:\\"); watcher.Created += (s, e) => Console.WriteLine($"Detected: {e.FullPath}"); Inject homebrew or game mods automatically after mounting:
To give you a responsible and useful response, let me clarify: