BorderLayout does not change its dimensions when resizing Window. But if you make a change in the size of the browser window, the BorderLayout immediately stretched boundaries Window. The error appears after clicking "maximizable" and then clicking "restore maximizable" of the Window

<window border="normal" title="demo" closable="true" sizable="true" maximizable="true">
<borderlayout vflex="1" hflex="1">
<north border="none">
bla-bla
</north>
<center border="true" style="border:1px solid red">
bla-bla
</center>
</borderlayout>
</window>