Save button is only partially visible on some large modals

Steps to reproduce

1. Go to <server>/xwiki/bin/view/Tour/
2. Click "Edit" for a Tour from 'Actions' column (e.g. for the Homepage Tour, force edit, if the case)
3. Click "Edit" button again to edit a step, thus opening a large modal
4. Observe the 'Save' button on the bottom of the modal (scroll down on the modal if the case)

Expected results

The 'Save' button is fully visible.

Actual results

The 'Save' button is only partially visible, even if scrolled all the way down, the lower half gets hidden under the browser window.

I've tried to resize the browser window, but it seems the modal is not so responsive.

The issue can be reproduced on Chrome 146, Edge 146 and Firefox 149 and on XWiki 15.10.16 as well (oldest version tested).