Our app has a custom file format and implements a Quicklook Thumbnailing extension. In iOS 16 (through to the latest beta 8 release) thumbnails are not generated in the Files app. And also are not returned for calls to QLThumbnailGenerator. Apple's sample app for this shows the same problem: https://developer.apple.com/documentation/uikit/view_controllers/building_a_document_browser_app_for_custom_file_formats I rolled back to iOS 15 to be sure and both our app and Apple's sample work there but fail in iOS 16. The console shows: error 13:34:59.136343-0700 LocalStorageFileProvider [ERROR] Creating internal error for "startFetchThumbnailOperationOverall", original error was: NSError: Cocoa 3328 "<private>" error 13:34:59.136801-0700 LocalStorageFileProvider [ERROR] Creating internal error for "startFetchThumbnailOperationOverall", original error was: NSError: Cocoa 3328 "<private>" error 13:34:59.137602-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.137767-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.137841-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.137948-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.138159-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.138283-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block error 13:34:59.620873-0700 LocalStorageFileProvider [ERROR] Creating internal error for "startFetchThumbnailOperationOverall", original error was: NSError: Cocoa 3328 "<private>" error 13:34:59.621362-0700 LocalStorageFileProvider [ERROR] Creating internal error for "startFetchThumbnailOperationOverall", original error was: NSError: Cocoa 3328 "<private>" error 13:34:59.622256-0700 com.apple.quicklook.ThumbnailsAgent Failing <private>, which did not get a per-thumbnail download completion block I filed feedback at the start of August (FB11066418) but have had no response. Is anyone else seeing this issue?