1. Show Undone toggles between views of racked and un-racked invoices.
2. Scan invoice barcodes and conveyor slot barcodes to assign rack locations to orders.
3. Display list of recently racked invoice locations or toggle to see orders awaiting rack assignment.
4. Scanning an invoice displays all the customer's ready invoices and their locations.
Review this to place the current order in a rack location nearby previously racked orders.