How to remove SBARS_SIZEGRIP from StatusBar

[kayon]

style := win.GetWindowLong(mw.StatusBar().Handle(), win.GWL_STYLE)
style &= ^win.SBARS_SIZEGRIP
win.SetWindowLong(mw.StatusBar().Handle(), win.GWL_STYLE, style)

It doesn't work. And there is no way to set MainWindow when it is created.