In the staff interface, when working with the collection management subrecord (whether in a resource, accession, or digital object record), there are two fields that have a grayed out asterisk (which typically means they are conditionally required, but neither tool tip explicitly states this): Processing Total Extent (text field) and Extent Type (drop-down field). If you enter a value for Processing Total Extent and leave Extent Type blank, you will not be able to save the record unless you also select an Extent Type. If you select an Extent Type, but you leave Processing Total Extent blank, you will be able to save the record. Perhaps some clarifying information could be added to the tool tips about what exactly is required depending on which scenario.