Mainstage 3.7 unable to delete Assignments items
I have so many Assignment & Mapping items/item groups that belong to old devices or were created by accident, I need to delete them, but the Delete Key action just flashes the screen, and the Edit → Delete is grayed out. What is puzzling is that there are 1 or 2 out of tens that can be deleted. I can't see the difference between why they can be and the rest cannot be.
Any help would be appreciated.
-Hiro
MacBook Pro 16″