Unfortunately in version 2021.10.0 the IntelliShell was getting very bad and makes the editor useless when you have to work with longer scripts.

I don't expect an immediate solution for better code-folding and syntax highlighting. But a quick and easy fix would be an option to Enable/Disable the Syntax Check. Then I would disable it and could continue using Studio 3T.

Note, even the 30 years old VBA-Editor in MS Excel provides this option, it should be a rather small change in the code of Studio 3T.