If you want to copy the URL’s href for the link while hovering the mouse over it, then try using the following code.
var $ = require('jquery');

$('body').on('mouseenter', 'a', function() {
updateStatusBarURL(this.href);
});

$('body').on('mouseleave', 'a', function() {
clearStatusBarURL();
});
For event delegation, you can use any library of your choice. However, it is recommended to use jQuery. Apart from that, you also need some logic to hover a mouse from one link to another. For that, you need to call updateStatusBarURL() function before calling clearStatusBarURL(). It will hide the status bar url even if you are hovering a link.