Since iPadOS 18, UIDocumentViewController has contained a document browser that shows a white page with rounded corners against a background of your choice, with the app name and "Create Document" buttons on the page. For instance, when you launch Pages, you see a white rounded page rectangle against a background of swirly orange, with “Choose a Template” and “Start Writing” buttons on the white page. In Numbers, there’s a green swirly background.
In apps built and run on iPadOS 27, however, the white page with rounded corners is entirely missing, making the browser screen very ugly, with the “New Document” button translucent directly against whatever background is set.
This can be reproduced simply by creating a new iOS "Document App" in Xcode 27 and building on iPadOS 27.
I assume this is a bug, since if you turn on exception breakpoints, you see the following exception breakpoint triggered during launch:
Exception = (NSException *) "[<_UIDocumentLaunchViewController 0x10732b200> valueForUndefinedKey:]: this class is not key value coding-compliant for the key _pageContainerView."
I have thus reported it as FB23418746. I am curious, though, whether it is a design decision to remove the page background on iPadOS 27, or whether I am missing some sort of setting in the UIDocumentViewController’s launch options for restoring the page. (I hope it’s not intentional, as I like the page, and without it, the black app name gets lost against darker or busier backgrounds.)
(I did try to include screenshots showing the issue when I first went to post this message, but doing so resulted in my IP address being blocked access to the forums for a week because of the forums’ new security measures.)