Debugger mades ESP8266 to reboot

[MarcoH2013]

Once I include debugger into my project, the ESP8266 will crash when I try to connect via telnet or websocket.
The RemoteDebug library works ok. Telnet and websocket is possible without a crash.

I already analyzed the crash stack without any result showing problems in my code.

• OS: [Windows]
• IDE [VSCode - PlatformIO]
• IDE Version [1.53.2 - 2.6.2]
• Board [ESP8266]

My code:

#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <WiFiUdp.h>

#include "RemoteDebug.h"
#include "RemoteDebugger.h"

RemoteDebug Debug;

void fun() {
  Debug.println("FUN!");
}

void setup() {
    Debug.begin((char *)"debugger"); // Initialize the WiFi server
    Debug.setResetCmdEnabled(true); // Enable the reset command
    Debug.showProfiler(false); // Profiler (Good to measure times, to optimize codes)
    Debug.showColors(true); // Colors

      Debug.initDebugger(debugGetDebuggerEnabled, debugHandleDebugger, debugGetHelpDebugger, debugProcessCmdDebugger); // Set the callbacks
      debugInitDebugger(&Debug); // Init the debugger

      debugAddFunctionVoid("fun", &fun);
}

void loop() {
    Debug.handle();
}

I hope someone can help me.