hello, im using this code to add tabs with iframes to tabpanel:

var addTab = function (tabPanel, id, tytul, url) {
    var tab = tabPanel.getComponent(id);
    if (!tab) {
        tab = tabPanel.add({
            id: id,
            title: tytul,
            closable: true,
            padding: 5,
            autoLoad: {
                showMask: true,
                url: url,
                mode: "iframe",
                maskMsg: "Ładowanie " + tytul + "..."
            }
        });
        tab.on("activate", function () {
            var item = MenuPanel1.menu.items.get(id + "_item");
            if (item) {
                MenuPanel1.setSelection(item);
            }
        }, this);
        tab.on("beforeclose", function () { Ext.getDom(TabPanel1.getActiveTab()).remove(); }, this);
    }
    tabPanel.setActiveTab(tab);
}
Problem is that browser memory usage is still groving even i close the tabs and reopen browser is taking more memory each time.
i tried with beforeclose event without luck.
How to clean DOM from closed tab? and maybe from other unused elements?