Trying to config limited extension access in user group

I'm trying to config a user group where the user has direct access to edit just one extension in order to format shipping labels, in this case the Como Shipping Labels extension. I've enabled access and modify permissions for extension/module/como_shippinglabels (among a few others), but the Extensions item doesn't show in the user's navigation menu. I'm using OC v3.0.2.0. Thanks for any input, the group permissions page is pretty confusing to me.

You need to give permission to the top level to get the menu item to show up. In this case I think it is "marketplace/extension"

Thank you, grgr, that did the trick!