Collapsible Collection Tree 2021

Hello All,
I have this same question, Is there a way to make the collection tree collapsible under the parent collection? I have so many sub-collections, I think it would look neater if someone could click the parent collection and the sub-collection would expand down.
Please advise.
-Kelsey

Continuing the discussion from Collection Tree: Collapsible list and changing parent collection in record: