How to get data from session?

Hi everybody! Sorry for my english, but i realy need a help.

In Visitor Log, i can see user’s data, ip, and provider. But also, i need to see his username. I can take it from php-session-file.

<?php $_SESSION['username'] = 'Jhon'; ?>

Like that.

So, what should i do?

Use custom variables: Custom Variables Analytics - Analytics Platform - Matomo