Maximum number of menu prompts?

I have been creating a menu structure for a large site using Enfold. There are 88 pages total, yet I cannot add more than 80 or so pages to the menu structure. Using Enfold’s Mega Menu feature makes this large a menu structure feasible. However, is there a physical limit to the number of pages that can be added to a WordPress menu? I might have inadvertently hit the limit if that is the case.

You can add menu prompts to the structure, but when you click the Save/Update button, the menu falls out of the ‘Manage Locations’ and removes it as the active Enfold Main Menu.