What does get_param(​gcb,'block​type') returns for block which are from non-installed toolbox ?

What does get_param(gcb,'blocktype') returns for block which are from non-installed toolbox ?

I thought it was reference but I found couple of them return EmptyBlock. Is there any documenation for it?

Answer 1

[Luca Ferro]

my guess is that yes, it is a subsystem reference but since the toolbox is not installed you don't have the source of the reference, hence the block shows as empty from a library point of view.