Steps to reproduce:
1. Configure extended metadata
2. Create unprivileged user that has role ROLE_UI_EVENTS_DETAILS_METADATA_VIEW but not has role ROLE_UI_EVENTS_DETAILS_METADATA_EDIT
3. Open "Event Details"
You don't see the tab "Metadata II" showing the extended metadata
You should see that tab
Workaround (if any):
Allow user to edit metadata, then it works