iOS 13 FileProvider, connection to service on pid 0

Our FileProvider-Extension used to work perfectly in previous iOS versions. Starting with iOS 13 we keep getting the following error randomly when accessing files (stored in the app group):


Error Domain=NSCocoaErrorDomain Code=4101 "Couldn’t communicate with a helper application." UserInfo={NSUnderlyingError=0x281edd1a0 {Error Domain=NSFileProviderInternalErrorDomain Code=7 "A connection to the extension “com.ourdomain.ourapp.DocumentProviderFileProvider” could not be made." UserInfo={NSLocalizedDescription=A connection to the extension “com.ourdomain.ourapp.DocumentProviderFileProvider” could not be made., NSUnderlyingError=0x281edcb10 {Error Domain=NSCocoaErrorDomain Code=4097 "connection to service on pid 0 named com.ourdomain.ourapp.DocumentProviderFileProvider.apple-extension-service" UserInfo={NSDebugDescription=connection to service on pid 0 named com.ourdomain.ourapp.DocumentProviderFileProvider.apple-extension-service}}}}}


Our FileProvider implements these methods:


func itemChanged(at url: URL)

func providePlaceholder(at url: URL, completionHandler: ((_ error: Error?) -> Void)?)

func startProvidingItem(at url: URL, completionHandler: @escaping (Error?) -> Void)

func stopProvidingItem(at url: URL)


The error happens rarely (only in ~1 of 100 tries). When it does, first the UI freezes (the device doesn't react to touches) for about 1 minute and then the error gets thrown by iOS. Sometimes if you retry to acces the file, the error goes away (file can be accessed), sometimes the error persists. This looks like a serious iOS-bug to me (at least in previous iOS versions the FileProvider, as mentioned, worked perfectly - and no changes have been made to the code).


Has anybody experienced similar issues in iOS 13 with a FileProvider-Extension?