UIViewController edges not extended behind top/bottom bars during a UINavigationController animation if it has a translucent UIToolbar subview

I'm displaying a translucent UIToolbar as a subview of a UIViewController which is a child of a UINavigationController (I don't use the UINavigationController toolbar as I want to subclass it).

Everything works fine but one thing: when I push another UIViewController on the UINavigationController stack, the next UIViewController edges are not extended behind the NavigationBar until the animation is over. The same issue occurs when the pop animation of the next UIViewController starts.

Side notes:
  • The NavigationBar is translucent (by default)

  • Both UIViewControllers are set to extend edges under top and bottom bars

  • The issue is not reproducible if the UIToolbar is not translucent (of if a tint is set).

  • The same issue occurs if the UINavigationController is inside a UITabBarController: the next UIViewController edges are not extended under the tabBar.

It's easily reproducible on iOS 12, iOS 13 and iOS 14 devices/simulators, with no code, just storyboard editing.

Here's a link to the StackOverflow post I've created a month ago with no feedback from the community:
https://stackoverflow.com/questions/63424459/uiviewcontroller-edges-not-extended-behind-top-bottom-bars-during-a-uinavigation
UIViewController edges not extended behind top/bottom bars during a UINavigationController animation if it has a translucent UIToolbar subview
 
 
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