New field items.hidden can't be filled during item creation. Possible only in item modification. (seen on unimarc, not tested in marc21) It seems that hidden field is not defined in C4:Items sub _koha_new_item, maybe also in other places. To test : Add an item marc subfield mapped whith hidden Add an new item whith 0 or 1 in the subfield items.hidden and the subfield are empty after validation Modify the item and add value for hidden items.hidden is then filled
wrong alert ; some people here added manually the hidden field to items table...