anchor.diff:    @override
     void discard() {
       _recycleCanvas(_canvas);
  +    _canvas = null;
       super.discard();
     }
   
  
positive.code:                 bitmapCanvas.bitmapPixelCount;
            }
            domRenderer.clearDom(rootElement!);
            if (_canvas is BitmapCanvas) {
              rootElement!.append(_canvas!.rootElement);
            }
            _canvas!.clear();
            picture.recordingCanvas!.apply(_canvas!, _optimalLocalCullRect);
          },
  
negative.code: List<_PaintRequest> _paintQueue = <_PaintRequest>[];
  
  void _recycleCanvas(EngineCanvas? canvas) {
    assert(canvas == null || !_recycledCanvases.contains(canvas));
    if (canvas is BitmapCanvas) {
      canvas.setElementCache(null);
      if (canvas.isReusable()) {
  