Reply To: Notice: Undefined offset: 11462 error when trying to change width of menu

I needed debug mode to be on for development purposes, but I have disabled it again now.

The error messages are gone, but it is not saving the design change, I can still not change, say, the menu “Katt” to be full-width.
It will just not save. It says it has been saved, but the design is still “Standard”, even when I changed it.