How to clone DOM SVG element in javascript?

Question

I want to store multiple HTMLCollection in an array but I don't want them to be dynamic.

var history = [];
var mysvg = document.getElementsByTagName("svg")[0];

this.saveToHistory = function(){
  history.push(mysvg);
}

For now, in my array history, the mysvg is a dynamic HTMLcollection. history[0] will be the same than history[1] even if when i called saveToHistory() history[0] was different from history[1]

I think making a copy of mysvg before pushing it in history is the way to solve this... but how can I do this?