Custom selectbox component?

Hiya. I’m trying to create a custom selectbox-like component, because the list items I’m dealing with are kinda special so I’d like to display some preview of each next to the select box. In addition. I’d like to have one or two other controls for special circumstances.

My react/JS foo is not all that strong, but I managed to create a custom component with an external fancy selectbox react component, the problem I’m having is that I need to specify the height of the whole component so the wrapping iframe can be adjusted accordingly by streamlit.
Ideally, I’d like to not have a lot of free space below my selectbox in case the user isn’t currently engaged in selecting an item, and have my item selection panel displayed over whatever is below my custom selectbox.

Any idea how to achive this? Or workarounds, creative hacks, etc?

Thanks!