When using a gravity form (multi-page, ajax) as a sticky modal for the bottom of the page, the generated anchor tag used to scroll interfears with the page scrolling.
The effect is when the user clicks the next button, the new page loads via ajax in the modal, but the gf js is trying to scroll to the top where the generated anchor tag is. But that's at the bottom of the page, so the page will auto scroll trying to keep up.
We can disable this behaviour with hooks. Add this to your themes function.php
Global disable
add_filter( 'gform_confirmation_anchor', '__return_false' );
Per form ID: Example form id of 5
add_filter( 'gform_confirmation_anchor_5', '__return_false' );