Scroll bars on a Delphi FMX tComboBox.ListBox not showing on a Mac

Question

I’m using Delphi 10.4.2 and trying to make the vertical scroll bar on the listbox of an FMX tCombox show all the time. It works fine on a PC but on a Mac the scrollbar disappears unless you’re actively scrolling the mouse wheel. If I put a regular tListbox on the form, I can make the vertical scroll bar appear constantly with the line ListBox1.AniCalculations.AutoShowing:=false; but I can’t seem to do the same for a tComboBox.Listbox. Nothing I can think of to try has any affect on the tCombox.ListBox. There must be some way to make the scroll bar stay; what am I missing?