Look here , maximized windows cover toolbar , maximized windows do not cover toolbar check option "above all " and uncheck option "Allow the windows overlap the Shelf ,
Apply.

Toolbar style , Gnome , Lxde etc... maximized windows
not cover Shelf.

Greetings:
Agust
Thanks Agust
I have tried this, but my problem is using the Restore/Maximize button. When you maximize it either goes under or over shelf, not stopping at shelf edge. I did set the windows manually and they remember the settings. So good enough.