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
Topic:
App & System Services
SubTopic:
General
Tags: