4 connections from one user

Hello, just one perhaps very easy question.
I noticed one strange thing few days ago.
When i log in Mikrotik through winbox i get 4 active connections (1 winbox + 3 telnet) connected at same time.
Can anyone explain that?

Tried from 3 different pc - same result.
Tried from other user from same group - just one connection - winbox, no telnet noticed.

Do you have Terminal windows open? These create telnet connections…