Method to put text in the Unity editor window

DrawStringGizmo.cs

public static class Drawing
{
    public static void DrawString(string text, Vector3 worldPos, Color? textColor = null, Color? backColor = null)
    {
        UnityEditor.Handles.BeginGUI();
        var restoreTextColor = GUI.color;
        var restoreBackColor = GUI.backgroundColor;
 
        GUI.color = textColor ?? Color.white;
        GUI.backgroundColor = backColor ?? Color.black;
 
        var view = UnityEditor.SceneView.currentDrawingSceneView;
        if (view != null && view.camera != null)
        {
            Vector3 screenPos = view.camera.WorldToScreenPoint(worldPos);
            if (screenPos.y < 0 || screenPos.y > Screen.height || screenPos.x < 0 || screenPos.x > Screen.width || screenPos.z < 0)
            {
                GUI.color = restoreTextColor;
                UnityEditor.Handles.EndGUI();
                return;
            }
            Vector2 size = GUI.skin.label.CalcSize(new GUIContent(text));            
            var r = new Rect(screenPos.x - (size.x / 2), -screenPos.y + view.position.height + 4, size.x, size.y);
            GUI.Box(r, text, EditorStyles.numberField);
            GUI.Label(r, text);
            GUI.color = restoreTextColor;
            GUI.backgroundColor = restoreBackColor;
        }
        UnityEditor.Handles.EndGUI();
    }
}