Adding NSVisualEffectViewMBS to container

In Adding NSVisualEffectViewMBS to Canvas - #5 by Thom_McGrath @Thom_McGrath tried to add vibrancy to a canvas. Unfortunately, there is no solution.

How do I use NSVisualEffectViewMBS in a container? The following code

dim win as NSWindowMBS = self.NSWindowMBS
dim view1 as new NSVisualEffectViewMBS(0, 0, self.Width, self.Height)
view1.autoresizesSubviews = true
view1.autoresizingMask = view1.NSViewMaxXMargin + view1.NSViewHeightSizable

win.contentView.addSubview(view1, -1, nil)

makes an NOE when used in the Open event of a container.

You can only get the NSView of a container after embedding it.