Yes this is the problem really, it’s not designed to be used with the header dropdown navigation mode, it’s designed to be used as a sidebar. Sidebar navigation is our default for new sites, and we plan to retroactively turn on the sidebar navigation mode on all our hosted sites. We don’t plan to further develop the old header dropdown mode, nor do we plan to carry two different navigation modes for admins.
@tobiaseigen may have more to say about this, but this is our position in the staff-experience team.