Woocommerce管理员未显示所有类别的产品

I have a weird problem I haven’t encountered before in WC backend: I have 23 products, they display just fine in the "all products" view. But when I click a category with 16 products, only 10 are listed, without pagination, although there is a not that 16 items are displaying.

Only way around that is to set screen options to show 10 items — then I get the pagination and the next 6 products are displayed on the second page.

But as I add more and more products, 10 items per page are simply too little, so I need a way to make it work as intended. Frontend is working fine though, which puzzles me even more.

P.S. I‘m on WP 4.9.8. and WC 3.4.5. — can‘t update to the latest WC yet because of the theme I use.