Checkout scrolling past footer

I also troubled the same problem Is there a solution?

This problem occurs in the update from 1.5.3 to 1.6.0

This is a feature. The order review box will now stick to the top of the browser window so that the place order button is always visible and the customer won’t have to search for it.

However, it looks like the background color isn’t being applied correctly here. Try opening the Customizer and saving a setting to see if that corrects it.

FYI if you want to disable this feature add something like this to your child themes functions.php file;

add_action( 'wp_enqueue_scripts', 'jk_remove_sticky_checkout', 99 );

function jk_remove_sticky_checkout() {
wp_dequeue_script( 'storefront-sticky-payment' );
}

Cheers