Steps to reproduce:

1. Create Discovery rule, with nested LLD, and item prototype for nested LLD
2. Execute LLD
3. Open discovered nested LLD -> Item prototypes
4. Click context menu, try to create dependent item

Result:
It is possible to open item / trigger creation forms using context menu for discovered item prototype. But not possible to add trigger or item.
See screenshot:

Expected:
Probably context menu should have both options disabled in such scenario