Code Connection fails

Problem: couldn't connect to Code Connection.

How to reproduce:

1. Start Code Connection, copy connect command string “/connect 192.168.2.3:19131”

2. Start Minecraft for Windows 10. Load a saved game.

3. Press t, paste connect command string “/connect 192.168.2.3:19131”, press Enter

4. The the following is displayed:

Connection established ws://192.168.2.3:19131

Connection closed

Versions：
OS: Windows 10 v1903
Minecraft for Windows 10 V1.12.101
code connection version 1.50

 

Same problem with Code Code connection from windows store and downloaded from https://education.minecraft.net/get-started/download/