fix: fix renderObject and element memory leaks.

kraken/lib/src/css/overflow.dart

@@ -105,6 +105,11 @@ mixin ElementOverflowMixin on ElementBase {
   KrakenScrollable? _scrollableX;
   KrakenScrollable? _scrollableY;
 
+  void disposeScrolling() {
+    _scrollableX = null;
+    _scrollableY = null;
+  }
+
   void updateRenderBoxModelWithOverflowX(ScrollListener scrollListener) {
     if (renderBoxModel is RenderSliverListLayout) {
       RenderSliverListLayout renderBoxModel = this.renderBoxModel as RenderSliverListLayout;
@@ -147,7 +152,7 @@ mixin ElementOverflowMixin on ElementBase {
       }
 
       renderBoxModel.scrollListener = scrollListener;
-      renderBoxModel.pointerListener = _pointerListener;
+      renderBoxModel.scrollPointerListener = _scrollPointerListener;
 
       if (renderBoxModel is RenderLayoutBox) {
         if (shouldScrolling) {
@@ -199,7 +204,7 @@ mixin ElementOverflowMixin on ElementBase {
       }
 
       renderBoxModel.scrollListener = scrollListener;
-      renderBoxModel.pointerListener = _pointerListener;
+      renderBoxModel.scrollPointerListener = _scrollPointerListener;
 
       if (renderBoxModel is RenderLayoutBox) {
         if (shouldScrolling) {
@@ -214,7 +219,7 @@ mixin ElementOverflowMixin on ElementBase {
   void scrollingContentBoxStyleListener(String property, String? original, String present) {
     RenderLayoutBox scrollingContentBox = (renderBoxModel as RenderLayoutBox).renderScrollingContent!;
     RenderStyle scrollingContentRenderStyle = scrollingContentBox.renderStyle;
-    
+
     switch (property) {
       case DISPLAY:
         scrollingContentRenderStyle.display = renderStyle.display;
@@ -334,7 +339,7 @@ mixin ElementOverflowMixin on ElementBase {
     outerLayoutBox.addAll(children);
   }
 
-  void _pointerListener(PointerEvent event) {
+  void _scrollPointerListener(PointerEvent event) {
     if (event is PointerDownEvent) {
       if (_scrollableX != null) {
         _scrollableX!.handlePointerDown(event);

kraken/lib/src/dom/element.dart

@@ -412,6 +412,9 @@ class Element extends Node
 
     // Remove renderBox.
     _removeRenderBoxModel(renderBoxModel!);
+
+    // Remove pointer listener
+    removeEventResponder(renderBoxModel!);
   }
 
   @override
@@ -555,6 +558,7 @@ class Element extends Node
     renderStyle.detach();
     style.dispose();
     properties.clear();
+    disposeScrolling();
 
     super.dispose();
   }
@@ -1703,8 +1707,8 @@ bool _hasIntersectionObserverEvent(Map eventHandlers) {
 void _detachRenderBoxModel(RenderBox renderBox) {
   if (renderBox.parent == null) return;
 
+  // Remove reference from parent
   RenderObject? parentRenderObject = renderBox.parent as RenderObject;
-
   if (parentRenderObject is RenderObjectWithChildMixin) {
     parentRenderObject.child = null; // RenderViewportBox
   } else if (parentRenderObject is ContainerRenderObjectMixin) {

kraken/lib/src/dom/event_handler.dart

@@ -37,6 +37,7 @@ mixin ElementEventMixin on EventTarget {
     renderBox.onLongPress = null;
     renderBox.getEventTarget = null;
     renderBox.dispatchEvent = null;
+    renderBox.getEventHandlers = null;
   }
 
   EventTarget getEventTarget() {

kraken/lib/src/gesture/scrollable.dart

@@ -239,7 +239,14 @@ class KrakenScrollable with _CustomTickerProviderStateMixin implements ScrollCon
 
 mixin RenderOverflowMixin on RenderBox {
   ScrollListener? scrollListener;
-  void Function(PointerEvent)? pointerListener;
+  void Function(PointerEvent)? scrollPointerListener;
+
+  void disposeScroll() {
+    scrollListener = null;
+    scrollPointerListener = null;
+    _scrollOffsetX = null;
+    _scrollOffsetY = null;
+  }
 
   bool _clipX = false;
   bool get clipX => _clipX;

kraken/lib/src/rendering/box_model.dart

@@ -172,6 +172,14 @@ class RenderLayoutBox extends RenderBoxModel
     }
   }
 
+  @override
+  void dispose() {
+    super.dispose();
+
+    paintingOrder.clear();
+    stickyChildren.clear();
+  }
+
   @override
   void markNeedsLayout() {
     super.markNeedsLayout();
@@ -682,7 +690,7 @@ class RenderBoxModel extends RenderBox
 
       // Copy overflow
       ..scrollListener = scrollListener
-      ..pointerListener = pointerListener
+      ..scrollPointerListener = scrollPointerListener
       ..clipX = clipX
       ..clipY = clipY
       ..enableScrollX = enableScrollX
@@ -1304,17 +1312,32 @@ class RenderBoxModel extends RenderBox
         renderStyle.backgroundAttachment == CSSBackgroundAttachmentType.local;
   }
 
+  void _detachAllChildren() {
+    if (this is RenderObjectWithChildMixin) {
+      (this as RenderObjectWithChildMixin).child = null;
+    } else if (this is ContainerRenderObjectMixin) {
+      (this as ContainerRenderObjectMixin).removeAll();
+    }
+  }
+
   /// Called when its corresponding element disposed
+  @mustCallSuper
   void dispose() {
     // Clear renderObjects in list when disposed to avoid memory leak
     if (fixedChildren.isNotEmpty) {
       fixedChildren.clear();
     }
 
+    // Dispose scroll behavior
+    disposeScroll();
+
     // Dispose box decoration painter.
     disposePainter();
     // Evict render decoration image cache.
     renderStyle.decoration?.image?.image.evict();
+
+    // Remove reference from childs
+    _detachAllChildren();
   }
 
   Offset getTotalScrollOffset() {
@@ -1428,8 +1451,8 @@ class RenderBoxModel extends RenderBox
   @override
   void handleEvent(PointerEvent event, HitTestEntry entry) {
     super.handleEvent(event, entry);
-    if (pointerListener != null) {
-      pointerListener!(event);
+    if (scrollPointerListener != null) {
+      scrollPointerListener!(event);
     }
   }
 

kraken/lib/src/rendering/flex.dart

@@ -197,6 +197,15 @@ class RenderFlexLayout extends RenderLayoutBox {
     return CSSFlex.isHorizontalFlexDirection(renderStyle.flexDirection);
   }
 
+  @override
+  void dispose() {
+    super.dispose();
+
+    flexLineBoxMetrics.clear();
+    childrenIntrinsicMainSizes.clear();
+    childrenOldConstraints.clear();
+  }
+
   double _getIntrinsicSize({
     FlexDirection? sizingDirection,
     double?

kraken/lib/src/rendering/flow.dart

@@ -175,6 +175,13 @@ class RenderFlowLayout extends RenderLayoutBox {
   /// Line boxes of flow layout
   List<_RunMetrics> lineBoxMetrics = <_RunMetrics>[];
 
+  @override
+  void dispose() {
+    super.dispose();
+
+    lineBoxMetrics.clear();
+  }
+
   @override
   void setupParentData(RenderBox child) {
     if (child.parentData is! RenderLayoutParentData) {

kraken/lib/src/rendering/sliver_list.dart

@@ -42,7 +42,7 @@ class RenderSliverListLayout extends RenderLayoutBox {
   }) : _renderSliverBoxChildManager = manager,
        _scrollListener = onScroll,
         super(renderStyle: renderStyle) {
-    pointerListener = _pointerListener;
+    scrollPointerListener = _scrollPointerListener;
     scrollable = KrakenScrollable(axisDirection: getAxisDirection(axis));
     axis = renderStyle.sliverDirection;
 
@@ -121,7 +121,7 @@ class RenderSliverListLayout extends RenderLayoutBox {
     }
   }
 
-  void _pointerListener(PointerEvent event) {
+  void _scrollPointerListener(PointerEvent event) {
     if (event is PointerDownEvent) {
       scrollable.handlePointerDown(event);
     }