diff --git a/Editor.Integrations/Odin/OdinFieldDrawer.cs b/Editor.Integrations/Odin/OdinFieldDrawer.cs
index c1b5bdcf..09e925d8 100644
--- a/Editor.Integrations/Odin/OdinFieldDrawer.cs
+++ b/Editor.Integrations/Odin/OdinFieldDrawer.cs
@@ -66,11 +66,7 @@ protected override void DrawPropertyLayout(GUIContent label)
             }
 
             _propertyTree.Update();
-
-            if (_propertyTree.ValidationRequired)
-            {
-                _propertyTree.RunValidation();
-            }
+            _propertyTree.RunValidationIfRequired();
 
             _labelOverrideContext.Label = label ?? GUIContent.none;
 
diff --git a/Editor.Integrations/Odin/OdinObjectDrawer.cs b/Editor.Integrations/Odin/OdinObjectDrawer.cs
index 22b9df79..9c6a207c 100644
--- a/Editor.Integrations/Odin/OdinObjectDrawer.cs
+++ b/Editor.Integrations/Odin/OdinObjectDrawer.cs
@@ -65,11 +65,7 @@ protected override void DrawPropertyLayout(GUIContent label)
             }
 
             _propertyTree.Update();
-
-            if (_propertyTree.ValidationRequired)
-            {
-                _propertyTree.RunValidation();
-            }
+            _propertyTree.RunValidationIfRequired();
 
             using (TriGuiHelper.PushEditorTarget(ValueEntry.SmartValue))
             {
diff --git a/Editor.Samples/TriSamplesWindow.cs b/Editor.Samples/TriSamplesWindow.cs
index 310e6d69..f8df9862 100644
--- a/Editor.Samples/TriSamplesWindow.cs
+++ b/Editor.Samples/TriSamplesWindow.cs
@@ -94,11 +94,7 @@ private void DrawElement()
 
                     _currentSerializedObject.UpdateIfRequiredOrScript();
                     _currentPropertyTree.Update();
-
-                    if (_currentPropertyTree.ValidationRequired)
-                    {
-                        _currentPropertyTree.RunValidation();
-                    }
+                    _currentPropertyTree.RunValidationIfRequired();
 
                     GUILayout.Space(10);
                     GUILayout.Label("Preview", EditorStyles.boldLabel);
@@ -106,8 +102,7 @@ private void DrawElement()
                     using (TriGuiHelper.PushEditorTarget(_current))
                     using (new GUILayout.VerticalScope(SampleWindowStyles.BoxWithPadding))
                     {
-                        var viewWidth = GUILayoutUtility.GetRect(0, 10000, 0, 0).width;
-                        _currentPropertyTree.Draw(viewWidth);
+                        _currentPropertyTree.Draw();
                     }
 
                     if (_currentSerializedObject.ApplyModifiedProperties())
diff --git a/Editor/Elements/TriHeaderGroupBaseElement.cs b/Editor/Elements/TriHeaderGroupBaseElement.cs
index a582c161..cbff466b 100644
--- a/Editor/Elements/TriHeaderGroupBaseElement.cs
+++ b/Editor/Elements/TriHeaderGroupBaseElement.cs
@@ -52,6 +52,8 @@ public sealed override void OnGUI(Rect position)
             {
                 xMin = contentBgRect.xMin + InsetLeft,
                 xMax = contentBgRect.xMax - InsetRight,
+                yMin = contentBgRect.yMin + InsetTop,
+                yMax = contentBgRect.yMax - InsetBottom,
                 height = contentHeight,
             };
 
diff --git a/Editor/TriEditor.cs b/Editor/TriEditor.cs
index fb615f75..4420144f 100644
--- a/Editor/TriEditor.cs
+++ b/Editor/TriEditor.cs
@@ -53,11 +53,7 @@ public override void OnInspectorGUI()
             serializedObject.UpdateIfRequiredOrScript();
 
             _inspector.Update();
-
-            if (_inspector.ValidationRequired)
-            {
-                _inspector.RunValidation();
-            }
+            _inspector.RunValidationIfRequired();
 
             using (TriGuiHelper.PushEditorTarget(target))
             {
diff --git a/Editor/TriPropertyTree.cs b/Editor/TriPropertyTree.cs
index 1f6c46eb..1fc0d83f 100644
--- a/Editor/TriPropertyTree.cs
+++ b/Editor/TriPropertyTree.cs
@@ -8,6 +8,7 @@ namespace TriInspector
     public abstract class TriPropertyTree
     {
         private TriPropertyElement _rootPropertyElement;
+        private Rect _cachedOuterRect = new Rect(0, 0, 0, 0);
 
         public TriPropertyDefinition RootPropertyDefinition { get; protected set; }
         public TriProperty RootProperty { get; protected set; }
@@ -39,6 +40,16 @@ public virtual bool ApplyChanges()
             return false;
         }
 
+        public void RunValidationIfRequired()
+        {
+            if (!ValidationRequired)
+            {
+                return;
+            }
+            
+            RunValidation();
+        }
+
         public void RunValidation()
         {
             ValidationRequired = false;
@@ -48,7 +59,7 @@ public void RunValidation()
             RequestRepaint();
         }
 
-        public virtual void Draw(float? viewWidth = null)
+        public virtual void Draw()
         {
             RepaintRequired = false;
 
@@ -62,19 +73,19 @@ public virtual void Draw(float? viewWidth = null)
             }
 
             _rootPropertyElement.Update();
-            var width = viewWidth ?? GUILayoutUtility.GetRect(0, 9999, 0, 0).width;
-            var height = _rootPropertyElement.GetHeight(width);
-            var rect = GUILayoutUtility.GetRect(width, height);
 
-            if (viewWidth == null)
-            {
-                rect.xMin += 3;
-            }
+            var rectOuter = GUILayoutUtility.GetRect(0, 9999, 0, 0);
+            _cachedOuterRect = Event.current.type == EventType.Layout ? _cachedOuterRect : rectOuter;
 
+            var rect = new Rect(_cachedOuterRect);
             rect = EditorGUI.IndentedRect(rect);
+            rect.height = _rootPropertyElement.GetHeight(rect.width);
+
             var oldIndent = EditorGUI.indentLevel;
             EditorGUI.indentLevel = 0;
 
+            GUILayoutUtility.GetRect(_cachedOuterRect.width, rect.height);
+
             _rootPropertyElement.OnGUI(rect);
 
             EditorGUI.indentLevel = oldIndent;
diff --git a/Editor/TriPropertyTreeForSerializedObject.cs b/Editor/TriPropertyTreeForSerializedObject.cs
index f62a56fe..f31fbf6d 100644
--- a/Editor/TriPropertyTreeForSerializedObject.cs
+++ b/Editor/TriPropertyTreeForSerializedObject.cs
@@ -56,11 +56,11 @@ public override void Update(bool forceUpdate = false)
             base.Update(forceUpdate);
         }
 
-        public override void Draw(float? viewWidth = null)
+        public override void Draw()
         {
             DrawMonoScriptProperty();
 
-            base.Draw(viewWidth);
+            base.Draw();
         }
 
         public override bool ApplyChanges()