I have an undefined statement or method after updating Unity

Questions & Answers
1

Console:

Assets/Editor/GridEditor.cs(45,30): error CS0117: UnityEditor.Undo' does not contain a definition for IncrementCurrentEventIndex’

Undo.IncrementCurrentEventIndex();

Thanx

2

You should replace that function call with

Undo.IncrementCurrentGroup();

If that’s not your script, you might look for an updated version or ask the author for an update.