StackView immediate transitions are broken

I stumbled upon several cases where using immediate transitions (i.e. pop(StackView.Immediate) with or without item argument) terribly breaks layout and visuals.

Nothing unfixable by simply resizing a window, pushing another page on a stack, or even simply causing a repaint event; but is very inconvenient and annoying.

It may look like this (header is displaced randomly):

TODO: fill in details.