how to enable automatic sharing of folders added/created in an already shared folder hiearchy?

I'm running

dovecot --version
	2.3.11.3 (502c39af9)

folder sharing is enabled & working.

as long as I manually enable enable sharing for each folder/subfolder.

e.g., if I enable sharing for each of:

sharedtopfolder
	subfolder1
	subfolder2

then all's good -- shared-to users can access according to set permissions.

BUT, if I drag any folder under that shared-hierarchy

e.g.,

sharedtopfolder
	subfolder1
	subfolder2

•   subfolder4

the just-added

subfolder3
subfolder4

are NOT shared.

They CAN be -- manually. And, as soon as they are, they're, again, usable by target users.

I'd like to have any/all newly-created, or dragged-in, folders under the already-shared "sharedtopfolder" to be **automatically** enabled for sharing.

how is that explicitly setup?

is it 'just' Dovecot config? &/or does it require some Sieve?