Mouseover/Mouseout bug

by Roman Bruckner

HTML

<html>
<head>
    <link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/jointjs/3.5.4/joint.css" />
</head>
<body>
      <!-- content -->
      <div id="paper"></div>

      <!-- dependencies -->
        <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.20/lodash.min.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.4.0/backbone.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/jointjs/3.5.4/joint.js"></script>
    
    </body>
</html>

JavaScript

const graph = new joint.dia.Graph({}, {
  cellNamespace: joint.shapes
});

const paper = new joint.dia.Paper({
  el: document.getElementById('paper'),
  width: 800,
  height: 900,
  model: graph,
  cellViewNamespace: joint.shapes,
  async: true,
  sorting: joint.dia.Paper.sorting.APPROX
});

const rect = new joint.shapes.standard.Rectangle({
  position: {
    x: 50,
    y: 50
  },
  size: {
    width: 100,
    height: 100
  },
  attrs: {
    body: {
      stroke: 'gray'
    }
  }
});


rect.clone().addTo(graph);

paper.on({
	'element:mouseover': function(v) {
     v.model.attr(['body', 'stroke'], 'red')
  },
  'element:mouseout': function(v) {  
     v.model.attr(['body', 'stroke'], 'gray')
  }
})