Add to cart URL with quantity?

See here

That’s not the solution I was looking for. I am not looking to show the quantity selector, I would like the button to immediately add to cart the product in a particular quantity, for example 3, so when the button is clicked it adds 3 to the cart.

Did you ever find a solution? I’m still looking to create a link with quantity. Right now I use:
https://domain.com/checkout/?post_type=product&add-to-cart=9

But I want to have that link add quantity 5 of product 9. Can I do that within the link?

Thanks.