In bookmarks, when updating with the entered filter, please hide the empty groups

[mc36]

Is your feature request related to a problem? Please describe.
i use qterminal's bookmark feature as a connection manager, so for, now i'm having hundreds of entries separated to a lot of groups..
everything is fine and i really enjoy the app, except when i type in a name, hit the tab, i have to hit a lot of unnecessary down keys to get through the empty groups...
pgup/pgdn works but does not help here because if jumps too much... a half a screen would be better here, much like in the terminal itself, when scrolling up/down with shift+pgup/pgdn....

Describe the solution you'd like
when preparing the list, you already hide the entries that does not match the typed filter...
could you please do an other iteration and hide the now empty groups?