Attaching TabBar hides Layout Header

I have a simple example with “2E” layout and tabbar attached to lower layout cell. When TabBar is attached to cell “b”, it’s header gets hidden, I have to force it to show by showHeader() to make it reappear.

    layout = new dhtmlXLayoutObject({
        parent: document.body,
        pattern: "2E",
        skin: "material",
        offsets: {
            top: 0,
            right: 0,
            bottom: 0,
            left: 0
        cells: [
                id: "a",
                text: "topBanner",
                header: false,
                height: 30,
                fix_size: [false, true],
                collapse: false
                id: "b",
                text: "",
                header: true,
                collapse: false,
                fix_size: [false, true],


    var tabsConf;
        tabsConf = [
            { id: "tab1", text: "ATM Cash Deposit by Branch", active: true },
            { id: "tab2", text: "ATM Cash Deposit by Customer" }

    var TabBar = layout.cells("b").attachTabbar({
        tabs: tabsConf


is that an intend behavior?


It is expected behavior. Layout hides the header to prevent header duplication ( as toolbar has a header-like area as well )