Button handlers not destroyd on window close?

[fermo111]

There is something odd with this snippet of code. Every time the window is opened, the _handlers array increases its length. Is it a bug or by design?

<button onclick="openDlg()">Open</button>

function openDlg(){
	win = new Ext.Window({
		title: 'New Window',
		width: 200,
		height: 200,
		modal: true,
		closeAction:'close',
		buttons: [{text: "OK"}]
	});
	
	win.on ('render', function () { 
		win.body.update(String(win.buttons[0].onClick._handlers.length));
	});
	
	win.show();
}

[hendricd]

Happy Buttons