A side note: It takes a VERY LONG time to load the “Data” tab to select the fields/etc, and there over sixteen thousand in our case, I had to change our PHP config to allow that form to post as it was limited to 5000 fields. Would it be possible to break that page up into smaller sections? I’ll post this as a feature request, whether you are interested in doing it or not at least it will be out there.
After removing that old (pre WooCommerce 2.00) _order_items metadata, everything indexed fine under 21.9, although I still am working through getting the searches up and running.
