Here link to docs about checkout links: https://help.shopify.com/en/manual/products/details/checkout-link
Today I found out that the option for several products has stopped working:
https://my-shop-name.myshopify.com/cart/36485954240671:3,31384149360662:1
I checked it on several stores and everywhere after clicking on the link gives a 404 not found page.
Works only if one product, for example:
https://my-shop-name.myshopify.com/cart/36485954240671:3
I also noticed that earlier the last comma was ignored. And now, if it is, it does not work again. For example, it doesn’t work like this right now:
https://my-shop-name.myshopify.com/cart/36485954240671:3,
It looks like a bug.