EditorWindow.HasOpenInstances

Проверяет открытость окна редактора.

using UnityEngine;
using UnityEditor;
using UnityEngine.UIElements;

public class HasOpenInstancesExample : EditorWindow
{
    [MenuItem("Examples/Has Open Instances")]
    static void Init()
    {
        var window = EditorWindow.GetWindow<HasOpenInstancesExample>();
        window.Show();
    }

    [MenuItem("Examples/Close Open Instances")]
    static void Close()
    {
        // Check if any window of type HasOpenInstancesExample is open.
        if (EditorWindow.HasOpenInstances<HasOpenInstancesExample>())
        {
            var window = EditorWindow.GetWindow(typeof(HasOpenInstancesExample));
            window.Close();
        }
    }

    void CreateGUI()
    {
        var label = new Label("Hello, World!");
        rootVisualElement.Add(label);
    }
}