Is it possible to write to an App Group's Container folder or UserDefaults from an iOS Thumbnail Extension or QuickLook Extension? It doesn't work. It does work for a Widget extension. I've added the App Group to the Entitlements of each extension. For writing a file to App Group Container I get Error Domain=NSCocoaErrorDomain Code=513 "Du hast nicht die Zugriffsrechte, um die Datei „quicklook 01 current.log“ im Ordner „DocumentInvestigation“ zu sichern." UserInfo={NSFilePath=/private/var/mobile/Containers/Shared/AppGroup/<redacted: the container UUID>/DocumentInvestigation/quicklook 01 current.log, NSUnderlyingError=0x28090bb10 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}} For setting App Group UserDefaults [User Defaults] Couldn't write values for keys ( &#9;&#9;example ) in CFPrefsPlistSource<0x2839cc700> (Domain: <redacted: the-group-identifier>, User: kCFPreferencesCurrentUser, ByHost: No, Container: (null), Contents Need Refresh: No): setting preferences outside an application's container requires user-preference-write or file-write-data sandbox access The use case is, that we are investigating an issue and would like to log to a file which we then can have customers send us.

We have an issue with documents stored on a shared iCloud drive folder, where the document reloads too often, sometimes even intermittently reverting to a stale older data. A very nice DTS lab during WWDC20 (with engineer Chen) could not solve the issue. Question to the forum crowd Does anybody also have this iCloud drive shared folder issue, and know a work around? How can we distinguish older data coming in from newer data? Here is a copy of the Feedback FB7772855 The Issue The NSDocument may intermittently reload with older data than was last saved, when storing an NSDocument in a iCloud Drive shared folder. This happens without any other device editing concurrently. Reproduce Create an iCloud Drive shared folder on a different AppleID Open and Run the attached sample project, or get it at https://github.com/hannesoid/iCloudSharedFolderDocumentIssue The attached sample project uses a text field which reads/stores a String as an NSDocument The attached sample project shows a list of log entries indicating what data was written and read by AppKit and when FileCoordination happens The attached sample project shows the NSDocument.lastModifiedDate Start typing into the the textfield and occasionally hit CMD+S (Save). Expected NSDocument should never read older data than what was last saved The file modification date should remain as last saved. Actual Sometimes the TextField reverts to a previous state In the log you see that there can be sequences where after Writing a certain Text to disk, a bit later an older state is read from disk. This is after filecoordination relinquished to a writer (probably icloud deamon). Then, a second or so later it reads again and then has the current data again. The file modification dates known by the NSDocument are also changed, dates get their milliseconds truncated after file coordination. System Tested on macOS 10.15.5

On two macs with 10.15.2 (19C57), we can't test an app for in app purchases# StepsBuild App in XcodeLaunch App from FinderIt launches, and quickly closesAfter a slight delay the sandbox Apple ID is requested (we expect this, as it needs to fetch a sandbox receipt)Enter a sandbox user Apple ID# Expected (it used to work)The os fetches a sandbox receipt for the appThe app launches# ActualThe System dialog comes claiming the app is damaged and needs to be deleted and redownloaded from the App storeWhen launching the app again, gatekeeper "verifies" the app and comes to the same conclusion.In the app, there is no MASReceiptAny advice?