Thanks for your answers, glad I'm not the only one :D I hope Eskimo will have a look at it and file a radar, I do not find out to file these now :-/

Interesting fact : if I use a trigger, it does not crash. Is a use a timer that flips a boolean trigger to mimic a loop, it does not crash either (just edited the POST)

Thanks to all of you for these answers and support, I appreciate ;-)

FYI, I tried with appearance, but safeAreaInsets are .zero and safeAreaLayoutGuide is still nil, that's a shame :-/      let appearance = UICollectionView.appearance(for: self.traitCollection,                            whenContainedInInstancesOf: [UIViewController.self, UINavigationController.self])     print(" \(appearance.safeAreaInsets) - \(appearance.safeAreaLayoutGuide)")

Thanks for your answer Claude31. For various reasons being : I need to send to the server the display area before even beginning to load a view That will not give me the insets for all orientation Besides, I can use the UIApplication.shared.windows.first?.safeAreaInsets to get the same result I guess ;-)