Hi,

I'm trying to create a UI using the dropdown component I found in source. However, this component is completely undocumented and missing from the schema file, so I'm running into issues figuring out how they actually work. I thought I'd drop an issue letting you know that it's missing from the schema.

Other issues I've found:

• Schema thinks that collapsible element cannot contain a children element

The dropdown component is now properly integrated in the schema, along with a few other fixes and corrections - thanks for bringing this up
Cheers