Bug? Some specific permissions can’t be edited

Reported on github here: https://github.com/publishpress/PublishPress-Permissions/issues/873

TLDR: Some specific permissions registered on Groups cannot be edited after they have been created, making testing and maintenance pretty cumbersome.

Steps to reproduce:

1. Create new Group
2. Add specific permissions as such: All post types | Read | Enable | All visibility statuses | Categories
3. Save
4. Check Capabilities – Roles that the Group says “Read(1)” which verifies the permissions were saved.
5. Click on “Read(1)”, which takes you to the Group again but the permission is not there.

Other types of permissions show up and may be edited.

The issue is not resolved by clearing cache.

Anyone seen this, is it a bug or am I missing something?

TIA.