Answered
Hide quantity input on single product
Where can I hide the quantity input on the single product page? I've used the setting "Customization Required". The Add To Card button is now hidden, but the quantity input is stille there.
See https://wpmayor.com/how-to-remove-quantity-field-from-woocommerce-product-page/
This is no solution. Because after customizing the product, the quantity input is also hidden. There we need it.