Selection of extension exposure.

[kjsii123]

How can I expose only the items I want when exposing extensions?

For example: If you look at the capture below, libs / base, libs / core, etc. are included in the extension and exposed.

However, as shown below, the extension is not exposed in the case of Lego. Which part should I change? Or is there a reference you can refer to?

[pelikhan]

You can set a flag

 "hidden": true

in pxt.json