Our code worked for iOS 14.x with Xcode 12.5.x. Updating to Xcode 13.x, we are receiving the following crash anytime we attempt to call collectionView.reloadData() or collectionView.setContentOffset(...). *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'the view returned from -collectionView:viewForSupplementaryElementOfKind:atIndexPath: does not match the element kind it is being used for. When asked for a view of element kind 'HomeSectionBackgroundView' the data source dequeued a view registered for the element kind '(null)'.' If we replace .reloadData() with .reloadItems(_: ) or .reconfigureItems(_: ), it fixes one of two errors, but how would we correct the .setContentOffset(...) crash?

THIS IS iOS 15 ONLY - THE SAME CODE WORKS FOR iOS 14.x USING XCODE 13.x, see below for details When using background elements with UICollectionViewFlowLayout and UICollectionViewCompositionalLayout in iOS 15 the following happens on .reloadData(), .reconfigureItems(...), and .reloadItems(...) only (initial load is fine): collectionView:viewForSupplementaryElementOfKind:atIndexPath: is called for background view Background view is dequeued SUCCESSFULLY viewForSupplementaryElementOfKind returns the view App crashes post viewForSupplementaryElementOfKind (sometimes up to seconds later) saying viewForSupplementaryElementOfKind has returned null I have verified: viewForSupplementaryElementOfKind IS dequeueing a cell The cell IS the correct element The element is returning viewForSupplementaryElementOfKind IS valid viewForSupplementaryElementOfKind loads correctly when the collectionView first loads; this only occurs on refreshing PLEASE, re-read the very top statement again before replying to ensure you are not replying "you/viewForSupplementaryElementOfKind is returning nil, check you are not returning nil". I will happily run additional test.