Same problem. Submitted a bug report (FB8889904)

Ok, here is the solution to this problem. Make sure that you use Xcode 12 beta 4 and iOS 14 beta 4 on your devices. Make sure that you have placeholder(in:) implemented. Make sure that you don't have placeholder(with:) because that's what the previous beta of Xcode was suggesting with autocompletion and without that you won't get your placeholder working. I think this whole problem is caused by the WidgetKit methods getting renamed but that's another story. As per the release notes, you need to set "Dead Code Stripping" to NO in your extension target's build settings. This is only necessary for the extension's target. When uploading your archive to the App Store Connect, uncheck "Include bitcode for iOS content". Delete your old build from a device when installing a new beta. That should do the trick.

If you check the NSItemProvider from PHPickerResult, you will see that it has "suggestedName" property. This will be your file name. I don't have any additional information about raw image data and creation date, sorry.

Usually when you include a framework into a project it is embedded only by a single target (e.g. the main app) and then is used by different extensions as well. With app clips things are different, they are installed separately from other targets. Therefore, you need to have the “Embed & Sign” option to be enabled for all relevant 3rd party frameworks on the App Clip target settings page in Xcode.

Yes, this is the same issue that is reported in multiple different threads. WidgetKit crashes when a widget is installed from a TestFlight build that was compiled with Xcode 12 beta 3.

I have checked the logs when installing the app from Xcode and when installing it from TestFlight. The difference is that WidgetKit is not able to get a timeline from a widget when the app is installed from TestFlight. That is the reason why the widget is not available for selection. My best guess is that there is something wrong with signing on TestFlight server. From TestFlight: default 11:12:14.851813+1000 chronod [com.mr-brightside.myParcel.ParcelWidget:ParcelWidget:medium:-7973698613864559631@321.0/148.0/20.2] reload: begin default 11:12:14.856270+1000 chronod [myParcel.ParcelWidget-B81718B65DEC] Session operation: getTimeline request. default 11:12:14.928178+1000 chronod [myParcel.ParcelWidget-B81718B65DEC] Session operation: getTimeline error result: <private> error 11:12:14.928569+1000 chronod [com.mr-brightside.myParcel.ParcelWidget:ParcelWidget] reload: failed with error Couldn’t communicate with a helper application.) From Xcode: default 11:19:45.639908+1000 chronod [com.mr-brightside.myParcel.ParcelWidget:ParcelWidget:medium:-7973698613864559631@321.0/148.0/20.2] reload: begin default 11:19:45.802217+1000 chronod [myParcel.ParcelWidget-A713984DD536] Session operation: getTimeline request. default 11:19:45.939728+1000 chronod [myParcel.ParcelWidget-A713984DD536] Session operation: getTimeline result. default 11:19:46.129838+1000 chronod [com.mr-brightside.myParcel.ParcelWidget:ParcelWidget] reload: succeeded with 1 entries default 11:19:46.131989+1000 chronod Task [84] [com.mr-brightside.myParcel.ParcelWidget:ParcelWidget:medium:-7973698613864559631@321.0/148.0/20.2] Completed Full logs are available in FB8122742

If I did not adopt the new TimelineProvider changes, I would not be able to run the app locally on a device from Xcode. I did adopt the changes, the issue is related to TestFlight.

I wish that was the case but that happened in Xcode 12 beta 3.

Please see the same problem here: https://developer.apple.com/forums/thread/655393

Could you please create a feedback and mention mine (FB8107534) as well? This way there is a better chance that Apple engineers will notice this and make this improvement.