In Firefox 9.40b1, in this example, after a few of click over the link “Click me” the link move from right to left and the have strange attribute:
linkhref=“null”
linkstyle=“float: right; margin-right: 10px;”
Same problem with Seamonkey 2.53.
No problem with Chrome and Edge.
<!DOCTYPE html>
<html><head>
<meta charset="utf-8">
<title>TEST</title>
</head>
<body></body>
<script>
"use strict";
var a=document.createElement("div");
a.id="main";
document.body.appendChild(a);
var res=document.createElement("div");
res.id="res";
a.appendChild(res);
var an=document.createElement("a");
an.textContent="Click me";
an.style.float="right";
an.style.marginRight="10px";
an.addEventListener("mouseup", e=>{
e.preventDefault();
e.stopPropagation();
if(e.button===0){
var a=document.getElementById("last");
a.innerHTML="new";
a.previousSibling.firstChild.textContent=new Date();
}
}, false);
res.insertBefore(an, res.firstChild);
a=document.createElement("div");
a.textContent="test";
a.id="last";
res.appendChild(a);
</script>
</html>