PDFKit, PDFView not displaying the PDFDocument full screen

Hi.
It's been a while I'm struggling with PDFkit issues, I hoped I will hear some improvements in WWDC20 but seems like it remains buggy.
Anyway, My issue is, I have an IBOutlet of type PDFView, in a ViewController embedded in UINavigationController, The issue is, I set the constraints to 0 from superView, in Interface Builder it goes under the navigationBar but when I run the app, it doesn't take the space that navigationBar occupies, the only solution is to hide the NavigatoinBar, bar that causes a jumpy effect.
I've also tried to create the PDFView Programatically, but it was still the same.
PDFKit, PDFView not displaying the PDFDocument full screen
 
 
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