Chrome bug？单击chrome 40.0.22x时触发鼠标移动事件

Question

I reproduced the effect in this pen

将鼠标移到灰色区域，并将其保持在那里，即使放手也是如此。您将看到鼠标计数器每秒都在增加。

HTML

<div> Please move your mouse over the red area and then remove your hand from the mouse, see the mouse movement counter increase every second. <br/><span></span></<div> 

CSS

div {
  position: absolute;
  width: 100%;
  height: 100%;
  background-color: grey;
  font-size: 20px;
}

b{
  font-size: 30px;
}

JS

mousemovements = 0;

$(function(){
  $("div").on("mousemove", function(){
    mousemovements += 1;
  $("span").html("<b>mouse moved: " + mousemovements+"   </b>");
})});

这个bug在firefox 35中不可见