[Koha] Vendor invoice - required field?

[Tom Hanstra]

When receiving a shipment in Koha Acquisitions, is the Vendor invoice a
required field in Koha now?

We have an older version of Koha and are upgrading.  We are finding that we
need to enter a Vendor Invoice number now which was not required in the
earlier version.  In general, invoice number makes little sense when paying
with credit cards anyway.

Is there any workaround for this?

Thanks
Tom Hanstra