I also installed the Vivid theme to see how some parts were constructed, I don't know if the loss of the drop down menu is due to this or to the upgrade to Gridbox. However, deleting the Vivid theme did not restore the menu behavior on the Maestro theme.
The administrator has disabled public write access.
Not in the editor. Just using Safari to navigate to the site.
The primary menu is at the top as expected.
Scroll down and the menu disappears as expected.
Scroll back up and the drop down menu does not appear (unexpected behavior).
The administrator has disabled public write access.
As we can see, on your pages, there is no sticky header plugin,
you may have removed it (it could not disappear by itself)
You need to re-add it and configure it
Best Regards,
Vyacheslav, Balbooa Support Team
The administrator has disabled public write access.