`$exerciseNumber_.$stepNumber.$type.tsx` loader repeatedly call `isPortAvailable`
I've just added a log to `isPortAvailable`.
this is the output:
```
[dev:server] 🐨 Let's get learning!
[…
I've seen it several times, app start without styles, only if i switch to problem or diff and go back to the app it looks ok
![without_styles](https://user-images.githubusercontent.com/3650909/22…