Is there a way to set a padding for the floating popup window ?

[Twix53791]

I tried to explore the setting which_key_floating_opts to set a padding. I would like just an "empty line" on top of the which key text. Is there a trick to achieve in some way something approaching? Which settings can be set in this field? Is there a link with https://vimhelp.org/popup.txt.html ?

Thanks for any clues!