Description
Adds functionality to the Purchase Order Gateway to allow the customer to upload a reference document and make the upload optional or required. You an also choose the file formats accepted. 
High Performance Order Storage (HPOS) Support
As of WooCommerce v8.0, HPOS has been the default. This stores order data in tables separate from the standard wp_post tables. If you’re still using Legacy Orders, this plugin will gracefully fall back to the legacy order storage, and when you migrate to HPOS, it will gracefully migrate the data as needed. 30
