The Event class, part of the UnityEngine namespace, allows you to handle user inputs such as key presses or mouse actions.

Let's update the method EventHandler inside the LevelInspector class:

private void EventHandler() {
    HandleUtility.AddDefaultControl(
    GUIUtility.GetControlID(FocusType.Passive));
    
    Vector3 mousePosition = Event.current.mousePosition;
    Debug.LogFormat("MousePos: {0}", mousePosition);
}

The variable Event.current has the information about the current event that's being processed in the Scene View.

From current, we are accessing the variable mousePosition to determine in which X and Y positions, relative to the Scene View coordinate system, the cursor of the mouse is found.

Save the changes and wait for Unity to compile. Now create a new level scene, select...