diff --git a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/GraphicalViewer.java b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/GraphicalViewer.java
index 13a5a412f..0ca7908ad 100644
--- a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/GraphicalViewer.java
+++ b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/GraphicalViewer.java
@@ -65,7 +65,8 @@ protected void setDefaultEventManager() {
 
 	protected GraphicalViewer(FigureCanvas canvas) {
 		m_canvas = canvas;
-		m_rootEditPart = new RootEditPart(this, getRootFigure());
+		m_rootEditPart = new RootEditPart(getRootFigure());
+		m_rootEditPart.setViewer(this);
 		m_rootEditPart.activate();
 		setRootEditPart(m_rootEditPart);
 	}
diff --git a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/RootEditPart.java b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/RootEditPart.java
index 6b3f16b62..1556bbf88 100644
--- a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/RootEditPart.java
+++ b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/graphical/RootEditPart.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2023 Google, Inc.
+ * Copyright (c) 2011, 2025 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -21,8 +21,10 @@
 import org.eclipse.wb.gef.graphical.tools.MarqueeSelectionTool;
 import org.eclipse.wb.internal.draw2d.IRootFigure;
 
+import org.eclipse.draw2d.IFigure;
 import org.eclipse.gef.EditPartViewer;
 import org.eclipse.gef.Request;
+import org.eclipse.gef.editparts.LayerManager;
 
 /**
  * A {@link RootEditPart} is the <i>root</i> of an {@link IEditPartViewer}. It bridges the gap
@@ -33,7 +35,7 @@
  * @author lobas_av
  * @coverage gef.graphical
  */
-public class RootEditPart extends GraphicalEditPart implements org.eclipse.gef.RootEditPart {
+public class RootEditPart extends GraphicalEditPart implements org.eclipse.gef.RootEditPart, LayerManager {
 	private IEditPartViewer m_viewer;
 	private final IRootFigure m_rootFigure;
 	private EditPart m_contentEditPart;
@@ -43,8 +45,7 @@ public class RootEditPart extends GraphicalEditPart implements org.eclipse.gef.R
 	// Constructor
 	//
 	////////////////////////////////////////////////////////////////////////////
-	public RootEditPart(IEditPartViewer viewer, IRootFigure rootFigure) {
-		m_viewer = viewer;
+	public RootEditPart(IRootFigure rootFigure) {
 		m_rootFigure = rootFigure;
 		createLayers();
 	}
@@ -88,7 +89,16 @@ public IEditPartViewer getViewer() {
 
 	@Override
 	public void setViewer(EditPartViewer viewer) {
+		if (m_viewer == viewer) {
+			return;
+		}
+		if (m_viewer != null) {
+			unregister();
+		}
 		m_viewer = (IEditPartViewer) viewer;
+		if (m_viewer != null) {
+			register();
+		}
 	}
 
 	/**
@@ -107,6 +117,11 @@ protected Figure createFigure() {
 		return null;
 	}
 
+	@Override
+	public Object getModel() {
+		return LayerManager.ID;
+	}
+
 	////////////////////////////////////////////////////////////////////////////
 	//
 	// IRootEditPart
@@ -152,4 +167,12 @@ public void setContents(org.eclipse.gef.EditPart contentEditPart) {
 	public Tool getDragTracker(Request request) {
 		return new MarqueeSelectionTool();
 	}
+
+	@Override
+	public IFigure getLayer(Object key) {
+		if (key instanceof String name) {
+			return m_rootFigure.getLayer(name);
+		}
+		return null;
+	}
 }
\ No newline at end of file
diff --git a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/RootEditPart.java b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/RootEditPart.java
index f83e0126f..aee2c6739 100644
--- a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/RootEditPart.java
+++ b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/RootEditPart.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2023 Google, Inc.
+ * Copyright (c) 2011, 2025 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -30,15 +30,6 @@ public class RootEditPart extends TreeEditPart implements org.eclipse.gef.RootEd
 	private IEditPartViewer m_viewer;
 	private TreeEditPart m_contentEditPart;
 
-	////////////////////////////////////////////////////////////////////////////
-	//
-	// Constructor
-	//
-	////////////////////////////////////////////////////////////////////////////
-	public RootEditPart(IEditPartViewer viewer) {
-		m_viewer = viewer;
-	}
-
 	////////////////////////////////////////////////////////////////////////////
 	//
 	// EditPart
diff --git a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/TreeViewer.java b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/TreeViewer.java
index 0a9add8a3..109691708 100644
--- a/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/TreeViewer.java
+++ b/org.eclipse.wb.core/src-gef/org/eclipse/wb/internal/gef/tree/TreeViewer.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2024 Google, Inc. and others.
+ * Copyright (c) 2011, 2025 Google, Inc. and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License 2.0 which is available at
@@ -61,7 +61,8 @@ public TreeViewer(Tree tree) {
 		// handle SWT events
 		m_eventManager = new TreeEventManager(m_tree, this);
 		// create root EditPart
-		m_rootEditPart = new RootEditPart(this);
+		m_rootEditPart = new RootEditPart();
+		m_rootEditPart.setViewer(this);
 		m_rootEditPart.activate();
 		setRootEditPart(m_rootEditPart);
 		// handle selection events