User adds a product to the cart -> Goes to checkout -> Log in into their customer account (in the checkout process).
Expected result: Customer is being logged in to their account with the items chosen previously.
Actual result: User is being redirected to an empty cart.
Using Magento ver. 2.2.4.
Just to give a bit more information... There are no logs in regards to this issue. Also, when adding a product to cart and logging in anywhere other than checkout works fine. So it might be worth mentioning that I use OnePageCheckout by Amasty.