Stop cart from moving with nav bar?

Hi! I have a nav bar that moves out of the way when the page is scrolled down on our webshop, and then comes back when scrolled up. Nothing strange there, works just as expected. But when the cart overlay (cart type: sidebar-right) is open, it too moves up with the nav bar as it moves out of the window, and seems that the cart wrapper/cart container has to be in the same block as the cart button which makes sure it has to move with the button. Is there any way around this? Video of behaviour:
Thanks in advance!

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