Sub-summary does not appear in browse mode
When I add a sub-summary to a layout, nothing happens in browse mode: the area of the sub-summary (let alone the fields that I included in layout mode) does not appear above the body.
One of the fields that I try to include in the sub-summary is a calculated foreign key. Could that be a problem? Removing it does not make the part appear though.
What are the most common reasons for such odd behavior? Do I need to manually check something to authorize sub-summaries to be displayed in browse mode? Am I missing something obvious?
Many thanks in advance.