Add callback in WindowDraggable to notify when the mouse button is released

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Inspector/MasterPreviewView.cs

-using System.Collections;
+using System;
+using System.Collections;
+using Object = UnityEngine.Object;
 
 namespace UnityEditor.ShaderGraph.Drawing.Inspector
 {
                 bottomContainer.Add(m_PreviewMeshPicker);
             }
             Add(bottomContainer);
-
-            Add(new ResizeBorderFrame(this) { name = "resizeBorderFrame"});
-
-            this.AddManipulator(new WindowDraggable());
         }
 
         MasterNode masterNode

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Manipulators/WindowDraggable.cs

-using System.Collections;
+using System;
+using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.Experimental.UIElements;
 
         Vector2 m_LocalMosueOffset;
         Rect m_PreviousParentRect;
+
+        public Action OnDragFinished;
 
         public WindowDraggable(bool resizeWithParentwindow = false)
         {
 
         void OnMouseUp(MouseUpEvent evt)
         {
+            bool emitDragFinishedEvent = m_Active;
+
             m_Active = false;
 
             if (target.HasMouseCapture())
             evt.StopPropagation();
 
             RefreshDocking();
+
+            if (emitDragFinishedEvent && OnDragFinished != null)
+            {
+                OnDragFinished();
+            }
         }
 
         void RefreshDocking()