ommitting line item discount column if no discounts are set

What version of Invoice Ninja are you running? ie v4.5 / v5 v5.11.36 What environment are you running? self-hosted Have you searched existing issues/requests? yes Additional context Having turned on the “Show Product Discount” option on Settings > Product Settings, the Discount column seems to show up on all invoice PDFs, even if no discount was entered. I would want to have the UI always show the discount column, so I always can enter a discount. But if I don’t enter a discount on any line item of a particular invoice, the discount column should not show up on the PDF. I rarely have to set discounts, but sometimes I do. Permanently turning on the discount column wastes space and adds clutter on many invoices that don't need it. Turning it on for a few invoices that need it and then turning it off again alters the preview of ALL invoices (including the ones that need it), which means the previews of those invoices are missing essential information to be understandable and …