Fab button group?

Hey all,
I’m not sure how far back I’m going here, but once upon a time on an age old version of Universal Dashboard there used to be a component equivalent to the New-UDFloatingActionButton we have today, however it allowed nested buttons inside it so it could be used as a sort of pop up menu in the bottom right, it was pretty useful.

I’m trying to achieve the same in the latest version but cant figure out an easy way to do it.
I’m able to add a fab button, but it’s singular with no nesting/grouping.

The docs state ‘FABs come in two types: regular, and extended.’
I was hoping extended is what I need but couldn’t see any parameters or anything extra to use that, maybe that’s a left over from days gone by?