HtmlTextField can't works in modal window

[Highmiao]

I use HtmlTextField to input English or Chinese, which works normally under canvas. root, but when I use HtmlTextField in modal window, the text cannot be displayed normally. Is this related to the layer?
let winLayer = canvas.getLayer(zebkit.ui.WinLayerMix.id);

    let win = new zebkit.ui.Window(
        'hello world',
        new zebkit.ui.web.HtmlTextField('hello world')
    );
    win.setBounds(10, 10, 500, 300);
    win.setSizeable(false);
    win.setBorder(new zebkit.draw.Border('gray', 1, 1));

I did a simple test, like the one above, where the text was not displayed in the input field.

[Highmiao]

I tried to solve the problem.
The HtmlTextField can't display text because I put theHtmlTextField in the winLayer.
let winLayer = canvas.getLayer(zebkit.ui.WinLayerMix.id);
The depth of the winLayer is 10000, and the depth of the HtmlTextField is 0, so the text in the HtmlTextField is obscured.
I solved the problem like this
let html_text_field = new zebkit.ui.web.HtmlTextField();
html_text_field.element.parentNode.style['z-index'] = 10001;