Generating invoice without decreasing stock capacity

Hi,

I'm using the stock feature to track the items in my store.
When I create an invoice, the stock is decreased, which is fine.

But I also offer pre-orders which are made seperately and should not adjust the stock.

It would be nice if I can create an invoice which would not affect the stock for this items.
Currently I add the items to the stock first and then create the invoice afterwards.

Best regards

Tobi