Scrollable tooltip

[LecrisUT]

Thanks @chrisjsewell for this project. I have been trying to configure sphinx-hoverxref to work on myst-parser with no success, so I am considering jumping ship. There is however one aspect that would be great to have from sphinx-hoverxref is the rendering of it.

More specifically the way you can hover over to the tooltip and then scroll through it. Not having it is a bit problematic since the top-level page can easily go out of bounds in both the vertical and horizontal direction. Any ideas on how hard would be to implement this?