title: How to react on link remove event in JointJS
body: <p>I use the following code to control the remove functionality on links. How can I intercept the remove event and prevent it if the link match a specific condition? </p>
  
  <pre><code>// add a remove button on hovered link
  this.paper.on("link:mouseenter", function(linkView) {
    let tools = [new joint.linkTools.Remove({ distance: 20 })];
  
    linkView.addTools(
      new joint.dia.ToolsView({
        name: "onhover",
        tools: tools
      })
    );
  });
  
  // remove button on hovered link
  this.paper.on("link:mouseleave", function(linkView) {
    if (!linkView.hasTools("onhover")) return;
    linkView.removeTools();
  });
  </code></pre>